positive - acting no - process printing plates are disclosed in which a stable visual or print - out image is obtained upon exposure of the plate to actinic radiation . the visual image is obtained by incorporation into the photosensitive layer , a dye which is irreversibly bleached upon exposure of the printing plate . for example , an acid which is generated upon exposure of a photopolymer to radiation may be used to bleach a dye of this invention . the visual or print - out images produced are useful in the production cycle and are stable to basic environments that may be encountered in the production setting .