Water-absorbent resin, absorbent body and absorbent article

Abstract

Provided is a water-absorbent resin capable of inhibiting backflow and leakage of a liquid absorbed by an absorbent body. When measured by a measurement method, this water-absorbent resin shows a repeated water absorption amount in an inclined state of 35 g or more. In the measurement method, 1.0 g of the water-absorbent resin is uniformly spread in a circular plastic petri dish having an inner diameter of 8.5 cm and a height of 1.7 cm. Subsequently, 30 g of physiological saline is supplied at once on the water-absorbent resin. Immediately thereafter, the petri dish is shaken 10 times from side to side and then allowed to stand for 3 minutes to form a swollen gel layer in which the physiological saline is absorbed by the water-absorbent resin. Separately, a device is prepared by fixing an acrylic plate having a flat main surface in such a manner that the main surface is at an angle of 30° to the horizontal plane. On the upper surface of the swollen gel layer, an air-through non-woven fabric, which has a weight per unit area of 21 g/m2 and cut into the same size as the inside of the petri dish, is placed. Then, the petri dish is stuck to the acrylic plate with tape to avoid slipping off. From a vertical height of approximately 1 cm at the center of the swollen gel layer in the petri dish, 5 g of the physiological saline is poured for 5 seconds using a macropipette. The pouring procedure is repeated 8 times at 1 minute intervals from the start of the physiological saline pouring. The amount of the liquid leaked from the petri dish is measured and subtracted from the amount (i.e., 40 g) of the poured physiological saline. The thus calculated mass of the physiological saline that is retained by the swollen gel layer is regarded as the repeated water absorption amount of the water-absorbent resin.

Dependencies are inferred from the claim text.