| abstract |
A highly absorbent polymer comprises water-insoluble, hydrophilic, crosslinked polymer particles having carboxyl or carboxylate groups, characterised in that said water-insoluble, hydrophilic, crosslinked polymer particles have an absorbing capacity satisfying the following requirements (i) to (iii), said absorbing capacity being imparted by enhancing the crosslinking density of the surfaces of said Water-insoluble, hydrophilic, crosslinked polymer particles: (i) the equilibrium swelling physiological saline absorption is 40 g/g (polymer) or more; (ii) the physiological saline absorption is 3 ml or more as determined by swelling 0.3 g of the polymer with physiological saline for 10 sec; and (iii) the time taken for 5ml of physiological saline to pass through a cylinder (internal diameter: 10mm) having a cross- sectional area of 0.785 cm<2> is 40 sec or less after 0.05 g of the polymer is packed together with physiological saline into the cylinder and swollen with the physiological saline, reaches an equilibrium swelling physiological saline absorption and settles in a swollen state. |