Patent ID: 8196510

Claim:
A method for the producing a flexographic printing plate, which has a base layer and a solid layer of a light sensitive material attached to the base layer, comprising producing an image in the layer of the light sensitive material by selective crosslinking, by insolating zones which are to be crosslinked with amplitude modulated laser light having a wavelength of 390 to 410 nm, and sweeping the layer of the light sensitive material with the amplitude modulated laser light to produced crosslinked zones in the layer of light sensitive material without the use of a mask, and, thereafter, removing zones which are not crosslinked to create the image in the solid layer of the light sensitive material, said solid layer of light sensitive material having a thickness between 0.5 to 2 mm and including at least one photoinitiator sensitive to said laser light at said wavelength, wherein the photoinitiator undergoes a photoreaction under effect of said laser light to bleach the layer of light sensitive material, wherein the bleaching renders the crosslinked zones transparent to said laser light in order to enable cross-linking throughout the thickness of the layer of light sensitive material.