| 摘要 |
The instant invention is directed to a process for the preparation of modified polyisocyanates which contain sulfonic acid alkyl ester groups and in which the isocyanate groups may be at least partly in the dimerized form, comprising: reacting isocyanatoaryl sulfonic acids having at least two isocyanate groups and wherein the isocyanate groups may be at least partly in the dimerized form, optionally as mixtures with mono and/or polyisocyanates which are free from sulfonic acid groups, with lactones at 0 DEG to 190 DEG C., wherein at least one of said lactones is a 6 to 9 membered ring lactone and the equivalent ratio of isocyanate groups, including any isocyanate groups present in the dimerized form, to sulfonic acid groups is greater than 1 and the equivalent ratio of lactone groups to sulfonic acid groups is from 0.1:1 to 10:1.
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