Controlled roughening of a photosensitive composition

In a photosensitive element wound in a roll comprising a flexible support bearing at least one layer of a photopolymer composition and a removable cover sheet, said support having greater adhesion than the cover sheet to the photosensitive element furthermore and the support is strippable from the photopolymer composition or transmits actinic radiation, whereby the improvement comprises the cover sheet having a roughened finish on its surface which faces toward the photosensitive composition and whereby the photosensitive composition follows contours of the cover sheet whereby the surface roughness of the photosensitive composition measured by Bekk roughness test is in a range from 20 seconds to 40 minutes.

In process of laminating under a vacuum a film supported photosensitive element to a substrate having a raised relief surface whereby the improvement comprises the photosensitive element on its surface which is laminated to the substrate having a roughened finish with the surface roughness in an average range from 2 to 11 microns, peak to valley distance.