PURPOSE: To obtain photocurable titled oligomer capable of providing flexible coating film, by the reaction between a specific hydroxyl group-contg. isocyanurate, a reaction product from a hydroxyl group-contg. acrylate and diisocyanate, etc., with one or more components -caprolacton-modified.

CONSTITUTION: The objective oligomer can be obtained by the reaction between (A) tris(2-hydroxyethyl)isocyanurate and/or an -caprolacton-modified polyol derived therefrom and (B) an ethylenic unsaturated monoisocyanate prepared by the reaction between a hydroxyalkyl(meth)acrylate and/or its -caprolacton- modified derivative and organic diisocyanate with either or both components containing -caprolacton-modified product(s).