Patent ID: 9671696
Date: 2017-06-06
CPC Classifications: B41N,G03F

Claim:
1. A digitally imageable, photopolymerizable, flexographic printing element which is developable using hydrocarbon-comprising washout media and which comprises—disposed one above another in the order stated—at least (A) a dimensionally stable support film having a thickness from 50 μm to 300 μm, (B) a photopolymerizable, relief-forming layer from 300 μm to 6000 μm in thickness, which is soluble or dispersible in organic solvents and which comprises at least one elastomeric binder, an ethylenically unsaturated monomer, and a photoinitiator or a photoinitiator system, (C) a transparent barrier layer for oxygen, (D) a laser-ablatable mask layer from 1 μm to 4 μm in thickness, which is soluble or dispersible in organic solvents and comprises at least an elastic binder and UV/VIS light-absorbing materials, the layer thickness and/or the amount of light-absorbing materials being made such that the layer has an optical density for UV/VIS radiation is 2 to 4, and (E) a removable top film, the barrier layer (C) being polar and being soluble in water and/or in water/alcohol mixtures comprising at least 50 wt % of water, and the barrier layer (C) having a thickness from 10 nm to 999 nm, wherein between the layers (C) and (D), the flexographic printing element comprises a transparent layer (X) for protecting the barrier layer (C) from laser radiation, the transparent layer (X) comprising at least one elastic, polymeric binder and having a thickness from 0.1 μm to 4 μm.