Polymeric materials suitable as dispersing resins

Abstract

Polymeric materials (I) are obtainable by reacting 1. a polymer II comprising a) from 80 to almost 100 mol % of a C.sub.1 -C.sub.25 -alkyl ester of an .alpha.,.beta.-unsaturated carboxylic acid, b) from 0 to 20 mol % of a further monomer, c) tetrahydrofuran hydroperoxide as polymerization initiator and, if required, d) a further polymerization initiator and/or regulator by means of which the majority of the polymer chains of the polymer II are terminated at one of their ends by a hydroxyl group, 2. with a polyfunctional isocyanate III to give a reaction product IV, the amount of isocyanate groups being from 1.2 to 3.0 mol per mol of hydroxyl groups of II, and 3. reacting IV with ammonia or with a compound V which has an amino function reactive toward isocyanates. The polymeric materials can be used as dispersing resins for pigment-containing coatings, in particular for the production of magnetic recording materials.

Dependencies are inferred from the claim text.