Imaging element for making a lithographic printing plate wherein that imaging element comprises a thermosensitive mask

摘要

According to the present invention there is provided an imaging element for making a lithographic printing plate comprising on a support having a hydrophilic surface a photosensitive layer and a thermosensitive layer, said thermosensitive layer being opaque to light for which said photosensitive layer has spectral sensitivity and said thermosensitive layer being capable of rendered transparent upon exposure to laser light characterised in that an intermediate layer being soluble or swellable in an aqueous medium is provided between said photosensitive layer and said thermosensitive layer.