A novel design for interdigitated band electrodes is described. The electrode is built by successive printing of conductive and insulating layers on a steel substrate. This geometry exhibits a high performance for the hypochlorite electrogeneration from seawater. The active chlorine concn. reached at the end of the electrolysis varies from 0.5 to 10 g L-1, depending on the no. of electrodes, their configuration in batch or single flow mode, the flow rate and the c.d. This geometry also limits scale development at the cathode. [on SciFinder (R)]