A printer for printing an interface onto a surface, the interface including visible text/graphics and coded data, the coded data being indicative of an identity of a region of the surface and of a plurality of locations on the surface, the printer comprising a data input module for receiving document data from a computer system, the interface being based at least partially on the document data, a coded data generator for generating the coded data using at least some of the document data, a printhead for printing the interface onto the surface, and an ink supply for supplying ink to the printhead, the ink supply comprising an ink set including at least one visible text/graphics ink and a coded data ink, wherein the or each visible text/graphics ink has an absorption of less than 20% at all wavelengths in the range of 800 to 900 nm, where 100% absorption is defined as the maximum absorption of the or each visible text/graphics ink when printed onto the surface.