Allophanate based dispersing agent

A copolymer obtained by:

• a. reacting at least one isocyanate (A) comprising at least one allophanate group and at least one active double bond with at least one isocyanate reactive component (B) to form an intermediate product (C), wherein the intermediate product (C) has an NCO content <0.2 wt. %, based to the overall weight of the intermediate product (C);
• and
• b. reacting the intermediate product (C) obtained in step a. with at least one active double bond reactive component (D) to obtain the copolymer;
• wherein the at least one isocyanate reactive component (B) is selected from the group consisting of monofunctional polyether amine (B1), monofunctional polyether alcohol (B2),—C6-C30 monofunctional alcohol (B3) and monofunctional polyester alcohol (B4);
• and wherein the at least one active double bond reactive component (D) is selected from the group consisting of imidazole, 1H-imidazol-1-amine, (1H-imidazol-1-yl)methanamine, (1H-imidazol-1-yl)ethan-1-amine, 3-(1H-imidazol-1-yl)propan-1-amine, 4-(1H-imidazol-1-yl)butan-1-amine, 5-(1H-imidazol-1-yl)pentan-1-amine, N-ethyl-2-(1H-imidazol-1-yl)ethan-1-amine, (1H-imidazol-1-yl)methanethiol, 2-(1H-imidazol-1-yl)ethane-1-thiol, 3-(1H-imidazol-1-yl)propane-1-thiol, 4-(1H-imidazol-1-yl)butane-1-thiol, (1H-1,2,3-triazol-1-yl)methanamine, 1H-1,2,3-triazole, 2-(1H-1,2,3-triazol-1-yl)ethan-1-amine, 3-(1H-1,2,3-triazol-1-yl)propan-1-amine, 4-(1H-1,2,3-triazol-1-yl)butan-1-amine, 5-(1H-1,2,3-triazol-1-yl)pentan-1-amine, (1H-1,2,3-triazol-1-yl)methanethiol, 2-(1H-1,2,3-triazol-1-yl)ethane-1-thiol, 3-(1H-1,2,3-triazol-1-yl)propane-1-thiol, 4-(1H-1,2,3-triazol-1-yl)butane-1-thiol, 5-(1H-1,2,3-triazol-1-yl)pentane-1-thiol, 4H-1,2,4-triazole, (4H-1,2,4-triazol-4-yl)methanamine, 2-(4H-1,2,4-triazol-4-yl)ethan-1-amine, 3-(4H-1,2,4-triazol-4-yl)propan-1-amine, 4-(4H-1,2,4-triazol-4-yl)butan-1-amine, 5-(4H-1,2,4-triazol-4-yl)pentan-1-amine, (4H-1,2,4-triazol-4-yl)methanethiol, 2-(4H-1,2,4-triazol-4-yl)ethane-1-thiol, 3-(4H-1,2,4-triazol-4-yl)propane-1-thiol, 4-(4H-1,2,4-triazol-4-yl)butane-1-thiol, 5-(4H-1,2,4-triazol-4-yl)pentane-1-thiol, (1H-tetrazol-1-yl)methanamine, 2-(1H-tetrazol-1-yl)ethan-1-amine, 3-(1H-tetrazol-1-yl)propan-1-amine, 4-(1H-tetrazol-1-yl)butan-1-amine, N-methyl-4-(1H-tetrazol-1-yl)butan-1-amine, 5-(1H-tetrazol-1-yl)pentan-1-amine, (1H-tetrazol-1-yl)methanethiol, 2-(1H-tetrazol-1-yl)ethane-1-thiol, 3-(1H-tetrazol-1-yl)propane-1-thiol, 4-(1H-tetrazol-1-yl)butane-1-thiol and 5-(1H-tetrazol-1-yl)pentane-1-thiol, N,N-diethyl-1,4-butanediamine, 1-(2-aminoethyl)piperazine, 2-(1-pyrrolidyl)-ethylamine, 4-amino-2-methoxy-pyrimidine, 2-dimethylaminoethanol, 1-(2-hydroxyethyl)piperazine, 4-(2-hydroxyethyl)morpholine, 2-mercaptopyrimidine, 2-mercaptobenzimidazole, N,N-dimethyl-1,3-propanediamine, 4-(2-aminoethyl)pyridine, 2-amino-6-methoxy-benzothiazole, 4-aminomethyl-pyridine, N,N-diallylmelamine, 3-amino-1,2,4-triazole, 1-(3-aminopropyl)imidazole, 4-(2-hydroxyethyl)pyridine, 1-(2-hydroxyethyl)imidazole and 3-mercapto-1,2,4-triazole, 1-(2-aminoethyl)imidazolidin-2-one, benzylamine, aniline, branched or linear (C2H5N)1-500 and salts thereof.