Water-soluble aspartate

#This application claims priority under 35 U.S.C. §119 to German patent application DE 10 2004 034 271.7, filed Jul. 15, 2004.

#The present invention relates to new water-soluble polyaspartic esters and also to their use as aqueous coating compositions.

#Two-component coating compositions comprising a polyisocyanate component binder in combination with a reactive component that is reactive toward isocyanate groups, in particular a polyhydroxyl component, have long been known. They are suitable for producing high-grade coatings, which can be made hard, elastic, abrasion-resistant and solvent-resistant.

#The invention accordingly provides hydrophilic polyaspartic esters of the general formula (I),

#where R is a C1-C4 alkyl radical, A and A′ in dependently of one another are hydrogen or methyl, X is an n-valent aliphatic, araliphatic or cycloaliphatic radical having 1 to 20 carbon atoms and optionally containing ether bridges, l and m are natural numbers from 0 to 10 whose sum l+m=1 to 20, and n is a natural number from 1 to 3.

#Preferably A and A′ are hydrogen.