US Patent 7282321 Lithographic printing method and presensitized plate

Disclosed is a presensitized plate composed of a support having thereon an image recording layer which includes:an infrared absorber (A) that is a cyanine dye having at least one fused ring composed of a nitrogen-containing heterocycle in combination with an aromatic ring or a second heterocycle, and having on the aromatic ring or second heterocycle an electron-withdrawing group or a heavy atom-containing group,a radical generator (B), anda radical-polymerizable compound (C),and which is removable with printing ink and/or dampening water.