Method for bump exposing relief image printing plates

A process of producing a relief image printing plate, the process comprising the steps of:

• a) providing a photosensitive printing element comprising:
• i) a support layer;
• ii) a layer of a photosensitive composition comprising:
• (a) one or more binders;
• (b) one or more monomers;
• (c) at least one photoinitiator;
• and
• (d) optionally, one or more ingredients selected from the group consisting of dyes, plasticizers, fillers, polymerization inhibitors and additives;
• and
• iii) optionally a release layer selected from the group consisting of matte coatings and slip film layers;
• and
• b) quenching dissolved oxygen in the photosensitive layer by pre-exposing the photosensitive layer to one or more sources of actinic radiation, wherein the range of wavelengths spanned by the one or more sources of actinic radiation is no more than about 20 nm;
• and
• c) imagewise exposing the photosensitive layer to actinic radiation to crosslink and cure the photosensitive layer;
• wherein the at least one photoinitiator is effective at the pre-exposure radiation wavelength and is present in the photosensitive composition in an amount sufficient to provide an optical density through the thickness of the photosensitive composition of between about 0.05 and 0.43 at a wavelength used to pre-expose the photosensitive composition.