Patent ID: 7927704

Claim:
A two-component coating composition comprising A) a polyisocyanate prepolymer having polyether groups attached via allophanate groups and B) an amino-functional polyaspartic ester of formula I) wherein X is an n-valent organic radical obtained by removing the primary amino groups from an n-valent polyamine, R 1 and R 2 are identical or different organic radicals which are inert towards isocyanate groups under the reaction conditions and n is a whole number of at least 2; wherein said polyisocyanate prepolymer A) is prepared by reacting A1) an aliphatic and/or cycloaliphatic polyisocyanate with A2) a polyhydroxy component comprising at least one polyether polyol to provide an NCO-functional polyurethane prepolymer and subsequently subjecting the urethane groups of said NCO-functional polyurethane prepolymer to partial or complete allophanatization by reacting it with A3) an aliphatic or cycloaliphatic polyisocyanate, which is the same or different from polyisocyanate A1), in the presence of an allophanate catalyst and optionally a stabilizer.