Abstract: A sheet material for bimetallic printing plate production comprises a base metal layer, a thin bimetallic layer comprising lithographically different metals, and a barrier layer between the base metal layer and the bimetallic layer. The barrier layer may be an anodic layer on the base metal layer or a film or sheet of suitable plastics material. The layers are laminated together and the barrier layer prevents corrosion by electrochemical action and by the decomposition products of the constituents of the adhesives used. Additionally, in the case where the barrier layer is of plastics material, the plate is resistant to fragmentation during printing. The sheet material may be produced in continuous lengths and results in printing plates which are relatively light in weight.