Patent ID: 9097974
Filing Date: 2015-08-04
Classification: G03F

Abstract:
1. A method for preparing a relief printing form from a photosensitive element, comprising the steps of: (a) forming an in-situ mask disposed above a layer of a photopolymerizable composition in the photosensitive element, wherein the photopolymerizable composition comprises a binder, an ethylenically unsaturated compound and a photoinitiator; (b) exposing the photopolymerizable layer to actinic radiation through the mask in an environment having an inert gas and a concentration of oxygen between 30,000 ppm and 7500 ppm, forming at least a polymerized portion and at least an unpolymerized portion; and, (c) treating by processing the element of step b) with at least one washout solution selected from organic solvent solution, aqueous solution, semi-aqueous solution, or water, whereby the unpolymerized portion is removed by the washout solution leaving a relief printing form having a plurality of raised surface elements made of the polymerized portion, with each raised surface element having a print surface area, and