| abstract |
An absorber 10 contains water-absorbent resin particles 10a and a fibrous substance, a medium particle diameter of the water-absorbent resin particles 10a is 250 to 600 µm, the water-absorbent resin particles 10a contain small-diameter particles having a particle diameter of 180 µm or less, and a falloff rate of a mixture of the small-diameter particles and the fibrous substance when the mixture is subjected to shaking treatment for 10 minutes is 20% by mass or less. |