Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: There are described novel rhodamine dye compounds and imaging members and imaging methods, including thermal imaging members and imaging methods, utilizing the compounds. The dye compounds exhibit a first color when in the crystalline form and a second color, different from the first color, when in the liquid, amorphous form.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: There are described novel rhodamine dye compounds and imaging members and imaging methods, including thermal imaging members and imaging methods, utilizing the compounds. The dye compounds exhibit a first color when in the crystalline form and a second color, different from the first color, when in the liquid, amorphous form.

Abstract: There are described novel rhodamine dye compounds and imaging members and imaging methods, including thermal imaging members and imaging methods, utilizing the compounds. The dye compounds exhibit a first color when in the crystalline form and a second color, different from the first color, when in the liquid, amorphous form.

Abstract: There is described a protective overcoat material comprising from about 40 weight percent to about 85 weight percent of poly(methyl methacrylate) having a Tg above about 100° C., from about 10 weight percent to about 50 weight percent of poly(ethyl methacrylate) having a Tg of from about 52° C. to about 65° C. and about 1 weight percent of a melt flow modifier. Also described are thermal image recording members which include a protective overcoat layer.

Abstract: There is described a method for forming an overcoat layer on a multilayer thermal imaging member by subjecting a layer of an overcoat composition including an oligomer having an acrylate function and a photoinitiator to ultraviolet or electron beam radiation. Multilayer thermal imaging members having an overcoat layer formed according to the method of the invention are also described.

Abstract: There is described a protective overcoat material comprising from about 40 weight percent to about 85 weight percent of poly(methyl methacrylate) having a Tg above about 100° C., from about 10 weight percent to about 50 weight percent of poly(ethyl methacrylate) having a Tg of from about 52° C. to about 65° C. and about 1 weight percent of a melt flow modifier. Also described are thermal image recording members which include a protective overcoat layer.

Abstract: The present invention provides a lithographic printing plate precursor element capable of being used on a printing press immediately after imagewise exposure without the requirement of bath processing. A preferred embodiment has in order (a) a substrate; and (b) a photoresist photohardenable upon imagewise exposure to actinic radiation, the photoresist comprising (i) a macromolecular organic binder; (ii) a photopolymerizable ethylenically unsaturated monomer having at least one terminal ethylenic group capable of forming a high polymer by chain-propagated polymerization, and (iii) a polymerization initiator activatable by actinic radiation; and (c) an on-press removable polyphosphate-containing overcoat. The polyphosphate-containing overcoat imparts the plate with a non-tacky surface and an enhanced resistance to the adverse influence of ambient humidity.

Abstract: The present invention provides a quenching overcoat useful for application onto a lithographic printing plate, the overcoat having incorporated therein a water or fountain soluble or dispersible crystalline compound. The overcoat may be used as an oxygen barrier and/or to provide a non-tacky surface on the printing plate. By the incorporation of the crystalline compound, on-press removability of the overcoat is facilitated.

Abstract: The present invention is directed to a method for the on-press development and printing of images. The method generally comprises the steps of providing a lithographic printing plate precursor element comprising a lithographic hydrophilic printing plate substrate, a photohardenable photoresist, and a layer of polymeric protective overcoat; imagewise exposing the precursor element to actinic radiation through said photoresist and overcoat layer sufficiently to photoharden the photoresist in exposed regions and provide a latent image in said photoresist layer; placing the precursor element onto a lithographic printing press; and running the press, whereby printing fluid effects removal of the overcoat and development of said latent image. In particular modes of practices, the method utilizes an overcoat having incorporated therein a water or fountain soluble or dispersible crystalline compound. The overcoat can be used as an oxygen barrier and/or to provide a non-tacky surface on the printing plate.

Abstract: A lithographic printing plate precursor for use on a printing press, with minimal or no additional processing after exposure to actinic radiation, comprises a printing plate substrate, a polymeric resist layer capable of imagewise photodegradation or photohardening, and a plurality of microencapsulated developers capable of blanket-wise promoting the washing out of either exposed or unexposed areas of the polymeric resist. The microencapsulated developers may be integrated into the polymeric resist layer, or may form a separate layer deposited atop the polymeric resist layer, or may be coated onto a separate sheet support capable of being brought into face-to-face contact with conventional printing plates.

Abstract: Described is the use of a plasticizing-permeation enhancing additive in negative-working, on-press developable lithographic printing plates. Briefly, a plasticizer, which is dispersible or soluble in press fountain and ink solutions and soluble in acrylic monomers and oligomers, are incorporated into a plate's photoresist at concentrations sufficient to enhance said resist's permeability to or diffusion by press solutions. Such additives make the photoresist more permeable to fountain solution prior to crosslinking, while being easily extracted with ink and fountain solution after crosslinking. In certain embodiments, a surfactant is added to facilitate the dispersion of hydrophobic remnants of removed resist material in the fountain solution, and thereby reduce scumming. Lithium salts may also be incorporated into the photoresist to disrupt hydrogen bonding of, for example, urethane acrylate polymers which tend to associate by hydrogen bonding.

Abstract: The present invention sets forth the incorporation of a substituted 2-phenyl-4,6-bis (trichloromethyl)-1,3,5-triazine in photoresists of lithographic printing plates for the purpose of promoting their shelf-life, room light stability, and developability. The present invention provides a photocurable composition comprising at least a photopolymerizable ethylenically unsaturated monomer having at least one terminal ethylenic group and capable of forming a polymer upon exposure to actinic radiation; and an s-triazine capable of initiating free radical polymerization of the photopolymerizable ethylenically unsaturated monomer and being represented by the following general formula [I]: ##STR1## wherein R.sub.1 is either OR.sub.4 or NR.sub.5 R.sub.6, wherein R.sub.5 and R.sub.6 may or may not be identical with each other, either R.sub.5 or R.sub.6 may represent hydrogen, and wherein R.sub.4 and at least one of R.sub.5 and R.sub.

Abstract: A lithographic printing plate for use on a printing press, with minimal or no additional processing after exposure to actinic radiation, comprises a printing plate substrate, a polymeric resist layer capable of imagewise photodegradation or photohardening, and a plurality of microencapsulated developers capable of blanket-wise promoting the washing out of either exposed or unexposed areas of the polymeric resist. The microencapsulated developers may be integrated into the polymeric resist layer, or may form a separate layer deposited atop the polymeric resist layer, or may be coated onto a separate sheet support capable of being brought into face-to-face contact with conventional printing plates.