A latent curing agent obtained by the reaction of a coumarin compound of the general formula (1), where X and Y can be independently H, an alkyl group, a heteroalkyl group, an aromatic group, a heteroaromatic group or an acetyl group and Z can be H, OH, an alkyl group, a heteroalkyl group, an aromatic group, a heteroaromatic group with an amine of the general formula (2), where “a” is 1 or 2, A can be an alkylene group, a heteroalkylene group, an aromatic group, a heteroaromatic group, and B can be an alkyl group (if a=1), an alkylene group (if a=2), a heteroalkyl group (if a=1), a heteroalkylene group (if a=2), an aromatic group, a heteroaromatic group, a hydroxyl group (if a=1), a secondary amino group (if a=2), O or S (if a=2), whereby B has the valency “a”, or where B alone or where A and B together form a ring system selected from an aliphatic ring system, a heteroaliphatic ring system, or an aromatic ring system, can be used for curable compositions with a polyepoxide which has at least 2 1,2-epoxide groups per molecule.