In a water-absorbing article (especially diaper) containing a water-absorbing resin as a water-absorbing agent, its “absolute absorption amount (g)”, “liquid absorption time (particularly the second and subsequent liquid absorption times)”, “return amount (g)” The present invention provides a water-absorbing resin (water-absorbing agent) that improves the “diffusion distance (%)” and a method for producing the same. In the particulate water-absorbing agent according to the present invention, CRC, a ratio of particles of 600 μm to 150 μm defined by standard sieve classification, SST, and a difference value of SST with respect to FST are in a predetermined range.吸水性樹脂を吸水剤として含む吸水性物品（特におむつ）において、その“絶対吸収量（ｇ）”、“吸液時間（特に２回目以降の吸液時間）”、“もどり量（ｇ）“、“拡散距離（％）”を向上させる、吸水性樹脂（吸水剤）及びその製造方法を提供する。 本発明に係る粒子状吸水剤は、ＣＲＣ、標準ふるい分級で規定される６００μｍ～１５０μｍの粒子の割合、ＳＳＴ、および、ＦＳＴに対するＳＳＴの差の値が所定の範囲にある。
