MODIFIED BLOCK POLYMERS, THEIR PREPARATION AND USE

The increasingly specific requirements regarding the properties of pigments, particularly in the printing sector, has made the development of specific dispersion, emulsification and coupling assistants necessary. According to the invention, novel substances which are suitable for a very wide variety of areas of application in the field of surfactants and can be employed, for example, in the preparation of azo pigments for improving the coloristic properties are obtained from oxyalkylates of aliphatic or cyclic, primarily primary diamines or polyamines or from block polymers (containing recurring structural units of the abovementioned oxyalkylate type) produced by prior linking of such oxyalkylates with dicarboxylic acids, by esterification of the terminal hydroxyl groups in these aminooxyalkylates using fatty acids or aromatic carboxylic acids and/or resin acids, and optionally subsequently reacting any free hydroxyl groups still present with dicarboxylic acids and sulphite to give the corresponding monoesters (containing anionic radicals).