Abstract: A surfactant selected from an acrylate-modified polydimethylsiloxane or a polyether-modified polydimethylsiloxane is used, together with at least a colorant and a UV-curable organic diluent, in a non-aqueous UV-curable ink composition suitable for ink jet printing. The use of this type of surfactant prevents the ink composition from causing the loss of more than 5% of the nozzles in an ink jet print head and enables the composition to provide a hole to area ratio of no more than 0.05. The present ink compositions have particular application in the printing of packaging for foodstuffs.