Abstract: A process for etching a metal or alloy surface which comprises applying an etch-resistant ink by ink jet printing to selected areas of the metal or alloy, exposing the etch-resistant ink to actinic radiation and/or particle beam radiation to effect polymerisation, optionally thermally treating the etch-resistant ink and then removing the exposed metal or alloy by a chemical etching process wherein the etch-resistant ink is substantially solvent-free and comprises the components: A) 30 to 90 parts acrylate-functional monomers; B) 0 to 50 parts metal adhesion promoting organic compound; C) 0 to 20 parts polymer and/or prepolymer; D) 0 to 20 parts radical initiator, E) 0 to 5 parts colorant; and F) 0 to 5 parts surfactant; wherein the ink has a viscosity of not greater than 200 cPs (mPa·s) at 40° C., all parts are by weight and the total number of parts A)+B)+C)+D)+E)+F)=100, provided that where the metal or alloy is supported by a non-etchable substrate, it does not constitute a printed circuit board.