Abstract: The present invention provides an infrared-sensitive composition including an initiator system comprising: (a) an infrared absorbing compound; (b) a radical producing compound; and (c) a carboxylic acid co-initiator compound. In some embodiments of the invention, the co-initiator is a monocarboxylic acid. In other embodiments of the present invention, the co-initiator is a polycarboxylic acid. The infrared-sensitive composition further includes a polymeric binder and a free radical polymerizable system consisting of at least one member selected from unsaturated free radical polymerizable monomers, oligomers which are free radical polymerizable, and polymers containing C═C bonds in the back bone and/or in the side chain groups. In some embodiments of the present invention, the acid number of the polymeric binder is 70 mg KOH/g or less. The present invention further provides a printing plate precursor, a process for preparing the printing plate and a method of producing an image.

Abstract: The present invention provides a radiation sensitive composition suitable for us in on-press developable printing plates. The radiation sensitive composition comprises an initiator system including an onium salt and a radiation absorber. The initiator system is combined with a polymerizable material, and a polymeric binder including polyethylene oxide segments.

Abstract: An IR-sensitive composition comprising, in addition to a polymeric binder, a free radical polymerizable system consisting of at least one member selected from unsaturated free radical polymerizable monomers, oligomers which are free radical polymerizable, and polymers containing C═C bonds in the back bone and/or in the side chain groups and an initiator system, wherein the initiator system comprises the following components: (a) at least one material capable of absorbing IR radiation, (b) at least one compound capable of producing radicals and (c) at least one hereto-substituted arylacetic acid co-initiator compound indicated by the following general structures: 1

Abstract: The present invention provides an initiator system including an infrared-absorbing compound that exhibits an electronic transition band in the near-infrared region, an initiator, and a metallocene compound. Upon exposure to infrared radiation, the initiator system is capable of producing radicals sufficient to initiate a photopolymerization reaction. Suitable infrared-absorbing compounds include indocyanine dyes, for example. Trihalomethyl triazine compounds and onium compounds are suitable initiators. Suitable metallocene compounds include ferrocenes and titanocenes. The present invention also provides an infrared-sensitive composition including an ethylenically unsaturated polymerizable component, an infrared-absorbing compound that exhibits an electronic transition band in the near-infrared region, an initiator, and a metallocene compound. The infrared-sensitive composition provides improved photospeed and sensitivity in some embodiments.

Abstract: Negative working thermally imageable elements useful as lithographic printing plate precursors and methods for their use are disclosed. The elements have a substrate, a layer of imageable composition over the substrate, and, optionally, an overcoat layer over the layer of imageable composition. The imageable composition has an allyl-functional polymeric binder. Optimum resolution and on-press performance can be attained without a post-exposure bake. The elements do not require a post-exposure bake and can be used in on-press development applications.

Abstract: The present invention relates to a polymerizable coating composition suitable for the manufacture of printing plates developable on-press. The coating composition comprises (i) a polymerizable compound and (ii) a polymeric binder comprising polyethylene oxide segments, wherein the polymeric binder is selected from the group consisting of at least one graft copolymer comprising a main chain polymer and polyethylene oxide side chains, a block copolymer having at least one polyethylene oxide block and at least one non-polyethylene oxide block, and a combination thereof. The invention is also directed to an imageable element comprising a substrate and the polymerizable coating composition.

Abstract: The present invention relates to IR-sensitive compositions containing an initiator system comprising: (a) at least one compound capable of absorbing IR light (b) at least one compound capable of producing radicals and (c) at least one polycarboxylic acid comprising an aromatic moiety substituted with a heteroatom selected from N, O and S and also at least two carboxyl groups wherein at least one of the carboxyl groups is bonded to the heteroatom via a methylene group. These compositions are inter alia extraordinarily suitable for the manufacture of printing plates.