The present invention relates to water dispersible core-shell microcapsules essentially free of formaldehyde. In particular it concerns oligomeric compositions comprising, and the microcapsules obtained from, particular reaction product between a polyamine component and a particular mixture of glyoxal and a C 2 2 dialkoxy ethanal. The present invention comprises also the invention s core shell microcapsules as part of a perfuming composition or of a perfuming consumer product.