Patent ID: 8632941

Claim:
A lithographic printing plate precursor comprising a substrate and an imageable layer disposed over the substrate, the imageable layer comprising: a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye, and a polymeric binder, wherein the infrared radiation absorbing dye is a cyanine dye that is represented by the following Structure (I): wherein: R 1 is L-R x wherein L is or a sulfur or nitrogen linking atom and R x represents a carbocyclic or heterocyclic aromatic group, a heterocyclic non-aromatic group, or an alkyl group having 1 to 12 carbon atoms, which carbocyclic or heterocyclic aromatic, heterocyclic non-aromatic, or alkyl group comprises one or more ethylenically unsaturated polymerizable groups, provided that when L is a nitrogen atom, L-R x represents N(R a )(R b ) wherein R a and R b are the same or different substituted or unsubstituted carbocyclic or heterocyclic aromatic groups, substituted or unsubstituted heterocyclic non-aromatic groups, or substituted or unsubstituted alkyl groups provided that R a and R b comprise one or more ethylenically unsaturated polymerizable groups, R 2 and R 3 each independently represent an organic group having 1 to 12 carbon atoms, R 4 and R 5 either both represent hydrogen atoms or, together with the carbon atoms to which they are bonded, comprise carbon atoms to form a five- or six-member carbocyclic ring, R 6 to R 9 each independently represents hydrogen, or an alkyl group or aryl group, and R 10 and R 11 independently represent hydrogen or halogen atoms, or alkyl, alkoxy, —COOR, —OR, —SR, or —NR 2 , groups, or R 10 and R 11 independently represent sufficient carbon atoms to form a fused aromatic ring, and A represents one or more optional counter ions sufficient to provide a neutral charge for the cyanine dye.