Addition compounds suitable as dispersing agents, processes for their preparation, their use and solids coated therewith

A process for preparing addition compounds and their salts comprising

• (a) reacting polyisocyanates having an average functionality of from 2.5 to 6 with monohydroxyl compounds of formula I
• Y--OH I
• wherein Y is selected from the group consisting of (i) aliphatic and cycloaliphatic hydrocarbon groups with 8 to 30 carbon atoms or in which the hydrogen atoms of the hydrocarbon groups are partly replaced by at least one substituent selected from the group consisting of halogens and aryl groups, and (ii) aliphatic, cycloaliphatic and aromatic groups with molecular weights of from 350 to 8000 which contain at least one group selected from the group consisting of --O-- and --COO-- or in which the hydrogen atoms of the aliphatic, cycloaliphatic and aromatic groups are partly replaced by halogen, in such a quantity that from 15 to 50% of the NCO groups are reacted,
• (b) reacting the reaction product from step (a) with at least one compound of formula II
• G--(E).sub.n II
• wherein E represents at least one group selected from the group consisting of --OH, --NH.sub.2 and --NHR, R represents an alkyl group having 1 to 4 carbon atoms, n represents 2 or 3, and G represents a group selected from the group consisting of aliphatic, cycloaliphatic and aromatic groups having a molecular weight of at most 3000 and containing at least two carbon atoms, in such a quantity that a further 15 to 45% of the NCO groups of the polyisocyanate originally put into the process are reacted but the sum of the degrees of NCO reaction in steps (a) and (b) amounts to from 40% to 75%,
• (c) reacting the reaction product from step (b) with at least one compound of the formula III
• Z--Q III
• wherein Q stands for --OH, --NH.sub.2, --SH, or --NHR', R' represents an alkyl group having 1 to 4 carbon atoms, and Z is an aliphatic group with 2 to 10 carbon atoms containing at least one tertiary amino group or comprises a heterocyclic group containing at least one basic ring nitrogen atom which does not carry a hydrogen atom, in such a quantity that at least one molecule of the compound Z--Q is available for each remaining isocyanate group unreacted in steps (a) and (b).