| abstract |
The invention relates to a hydrophilic hydrogel with a high swelling capacit y. The inventive hydrogel is based on (co)polymerised monomers or graft (co)polymers and is produced by a) radical (co)polymerisation of one or more hydrophilic monomers or graft (co)polymerisation of one or more hydrophilic monomers to a graft base, the average degree of neutralisation of the monome rs containing the acid groups being 0 to 40 mol. %, b) reducing the acidic hydrogel, c) neutralising the acidic hydrogel to an end degree of neutralisation of 50 85 mol. % by adding a neutralising agent, d) drying, milling, and sieving the hydrogel particles, the hydrogel having a centrifug e retention of at least 29g/g for a 0.9 % aqueous NaCl solution and a swelling height of at least 3.5 cm with vertical absorption (1 g) and an extractable content (16 h-value) of less than 5 % or a centrifuge retention of at least 23g/g for a 0.9 % aqueous NaCl solution and a swelling height of at least 5 cm with vertical absorption (3 g) and an extractable content (16 h-value) of le ss than 5 % t. |