A positive working photosensitive film resist material suitable for multiple image-wise exposure comprises, on a dimensionally stable base film, a photosensitive coating which contains (a) a polymer which possesses aromatic or hetero-aromatic o-nitrocarbinol ester groups (for example o-nitrobenzyl acrylate units) and which can be washed out, after exposure, with an alkaline solvent, and (b) a transparent plasticizer compatible with (a). The product may be used as photopolymer dry film resist material in the production of electrical conductor boards, chemically milled fine-line parts, and identification plates.