Patent ID: 6916878

Claim:
An aqueous dispersion substantially free from volatile organic compounds, comprising (A) at least one block copolymer prepared by two-stage or multistage free-radical copolymerization in an aqueous medium of a) at least one olefinically unsaturated monomer selected from the group consisting of hydrophilic and hydrophobic olefinically unsaturated monomers, and b) at least one olefinically unsaturated monomer different than the olefinically unsaturated monomer (a) and of the general formula R 1 R 2 C═CR 3 R 4 (I) in which the radicals R 1 , R 2 , R 3 and R 4 each independently of one another are hydrogen atoms or substituted or unsubstituted alkyl, cycloalkyl, alkylcycloalkyl, cycloalkylalkyl, aryl, alkylaryl, cycloalkylaryl, arylalkyl or arylcycloalkyl radicals, with the proviso that at least two of the variables R 1 , R 2 , R 3 and R 4 are substituted or unsubstituted aryl, arylalkyl or arylcycloalkyl radicals; and (B) hydrophilic nanoparticles.