Abstract: Images can be provided using a method comprising thermally imaging a negative-working imageable element to provide an imaged element with exposed regions and non-exposed regions, the exposed regions consisting essentially of coalesced core-shell particles, and developing the imaged element on-press to remove only the non-exposed regions using a lithographic printing ink, fountain solution, or both. The imageable element comprises a single thermally-sensitive imageable layer consisting essentially of an infrared radiation absorbing compound and core-shell particles that coalesce upon thermal imaging. The core of the core-shell particles is composed of a hydrophobic thermoplastic polymer, the shell of the core-shell particles is composed of a hydrophilic polymer that is covalently bonded to the core hydrophobic thermoplastic polymer, and the thermally-sensitive imageable layer comprises less than 10 weight % of free polymer.

Abstract: Negative-working imageable elements have a hydrophilic substrate and a single thermally-sensitive imageable layer. This layer can include an infrared radiation absorbing compound and polymeric particles that coalesce upon thermal imaging. These coalesceable polymeric particles comprise a thermoplastic polymer and a colorant to provide improved visible contrast between exposed and non-exposed regions in the imaged element, such as lithographic printing plates.

Abstract: A singe- or multilayer lithographic printing plate precursor comprises on a substrate a radiation-sensitive coating that comprises a copolymer soluble or dispersible in aqueous alkaline solution and comprising (meth)acryl recurring units, imide recurring units, and amide recurring units derived from corresponding ethylenically unsaturated polymerizable monomers; the copolymer provides increased chemical resistance for the lithographic printing plate precursors which can be negatively or positively working.

Abstract: A method is described for producing an imaged lithographic printing plate, wherein the developer comprises a hydrophilic polymer comprising (m1) structural units derived from at least one compound comprising both a polyalkylene oxide chain and a free radical polymerizable group, and (m2) structural units derived from at least one compound copolymerizable with the free radical polymerizable group of (i) and comprising at least one functional group with pKs<5.

Abstract: Single layer IR-sensitive negative-working imageable elements include thermally coalesceable core-shell particles without a polymeric binder in an imageable layer. Thermal imaging causes coalescence of the particles in imaged regions while non-imaged regions can be removed with plain water or an aqueous solution containing an acidic polymer.

Abstract: The present invention provides a positive-working, thermally imageable element generally comprising a multi-layered imageable coating. The invention provides an imageable element comprising a substrate, an ink-receptive top layer, and an underlayer, the underlayer including a specific copolymer described herein. The copolymer can be a polymer comprising constitutional units derived from: a) a monomer having a cyclic urea group; b) a monomer comprising an N-substituted maleimide; c) a (meth)acrylamide or (meth)acrylate monomer; and d) a (meth)acrylic acid or vinyl benzoic acid monomer. In another embodiment, the copolymer can be a polymer comprising constitutional units derived from: a) a monomer having a cyclic urea group; b) a (meth)acrylic acid or vinyl benzoic acid monomer; c) and a (meth)acrylonitrile monomer. The imageable element may be used to prepare a lithographic printing plate that is resistant to press chemistry and can optionally be baked to increase press runlength.

Abstract: The present invention provides a positive-working, thermally imageable element generally comprising a multi-layered imageable coating. The invention provides an imageable element comprising a substrate, an ink-receptive top layer, and an underlayer, the underlayer including a specific copolymer described herein. The copolymer can be a polymer comprising constitutional units derived from: a) a monomer having a cyclic urea group; b) a monomer comprising an N-substituted maleimide; c) a (meth)acrylamide or (meth)acrylate monomer; and d) a (meth)acrylic acid or vinyl benzoic acid monomer. In another embodiment, the copolymer can be a polymer comprising constitutional units derived from: a) a monomer having a cyclic urea group; b) a (meth)acrylic acid or vinyl benzoic acid monomer; c) and a (meth)acrylonitrile monomer. The imageable element may be used to prepare a lithographic printing plate that is resistant to press chemistry and can optionally be baked to increase press runlength.

Abstract: Multilayer, positive working, thermally imageable elements are disclosed. The elements produce bakeable lithographic printing plates that are resistant to press chemistries. The elements have a substrate, an underlayer, and a top layer. The underlayer comprises a resin or resins having activated methylol and/or activated alkylated methylol groups, such as a resole resin, and a polymeric material that comprises, in polymerized form, (a) methacrylic acid; (b) N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; and (c) one or more monomers of the structure: in which: R1 is H or methyl; X is —(CH2)n—, where n is an integer from 2 to 12; —(CH2—CH2—O)p—CH2—CH2—, where p is an integer from 1 to 3; or —Si(R?)(R?)— where R? and R? are each independently methyl or ethyl; and m is 1, 2, or 3.

Abstract: Multilayer, positive working, thermally imageable elements are disclosed. The elements produce bakeable lithographic printing plates that are resistant to press chemistries. The elements have a substrate, an underlayer, and a top layer. The underlayer comprises a resin or resins having activated methylol and/or activated alkylated methylol groups, such as a resole resin, and a polymeric material that comprises, in polymerized form, (a) methacrylic acid; (b) N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; and (c) one or more monomers of the structure: in which: R1 is H or methyl; X is —(CH2)n—, where n is an integer from 2 to 12; —(CH2—CH2—O)p—CH2—CH2—, where p is an integer from 1 to 3; or —Si(R?)(R?)— where R? and R? are each independently methyl or ethyl; and m is 1, 2, or 3.

Abstract: A coating solution useful in the preparation of printing plate precursors comprises: a) a radiation sensitive composition C comprising a phenolic resin; b) at least one thermoplastic polymer P which has a solubility in aqueous alkaline media ranging from sparingly soluble to insoluble; c) a first solvent component A which is capable of solubilizing both composition C and thermoplastic polymer P; d) a second solvent component B having a volatility less than component A, wherein component B is capable of volatilizing composition C but not thermoplastic polymer P, and composition C and thermoplastic P are homogeneously dissolved in a mixture of components A and B; and e) at least one further polymer AP having a higher molecular weight than the phenolic resin of composition C, wherein polymer AB is miscible with the phenolic resin and immiscible with thermoplastic polymer P.

Abstract: A radiation-sensitive composition for use in printing plates is described. The composition comprises: (a) at least one novolak; (b) at least one naphthoquinone diazide derivative; and (c) a copolymer comprising units A, B, and a unit C comprising a cyclic terminal urea group, wherein unit A is present in an amount of about 5 to about 50 mol % and has the formula wherein R1 is selected such that the homopolymer of A is alkali-soluble, unit B is present in an amount of about 20 to about 70 mol % and has the following formula wherein R2 is selected such that the homopolymer of B has a glass transition temperature greater than 100° C., preferably a glass transition temperature in the range from about 100 to about 380° C.

Abstract: A radiation-sensitive composition for use in printing plates is described.

Abstract: A coating solution useful in the preparation of printing plate precursors comprises:

Abstract: A method for producing printing plate precursors by dual-feed technology is described. The obtained printing plate precursors contain polymer particles in the photosensitive layer and show high print run stability.

Abstract: Copolymers useful in radiation-sensitive layers of printing plates have the units A, B and C wherein unit A is present in an amount of 5 to a maximum of 50 mol % and R1 and R4 are selected such that the homopolymer of A is alkali-soluble, B is present in an amount of 20-70 mol % and R2, R6 and R7 are selected such that the homopolymer of B has a high glass transition temperature, and C is present in an amount of 10-50 mol % and R3 and R5 are selected such that the homopolymer of C is water-soluble and that unit A is different from unit C.

Abstract: A radiation-sensitive composition, positive-working coating compositions useful for the preparation of lithographic printing plates and lithographic printing plate precursors comprising the composition are disclosed. The composition comprises at least one quinonediazide compound and at least one carboxylic copolymer. The compositions produce lithographic printing plates that show high print run stability.

Abstract: Radiation-sensitive compositions comprise at least one novolak, at least one naphthoquinone diazide derivative and a copolymer; the copolymer consisting of the units A, B and C wherein unit A is present in an amount of 5 to a maximum of 50 mol % and R1 and R4 are selected such that the homopolymer of A is alkali-soluble, B is present in an amount of 20 to 70 mol % and R2, R6 and R7 are selected such that the homopolymer of B has a high glass transition temperature, and C is present in an amount of 10 to 50 mol % and R3 and R5 are selected such that the homopolymer of C is water-soluble and that unit A is different from unit C. Furthermore, the invention describes printing plates produced therefrom.

Abstract: A method for producing printing plate precursors by dual-feed technology is described. The obtained printing plate precursors contain polymer particles in the photosensitive layer and show high print run stability.

Abstract: Imageable elements useful as lithographic printing members are disclosed. The elements contain a substrate, an underlayer, and a top layer. The underlayer contains a combination of polymeric materials that provides resistance both to fountain solution and to aggressive washes, such as a UV wash. The underlayer can be used in either thermally imageable or photochemically imageable elements.

Abstract: A radiation-sensitive composition for use in printing plates is described. The composition comprises: (a) at least one novolak; (b) at least one naphthoquinone diazide derivative; and (c) a copolymer comprising units A, B, and a unit C comprising a cyclic terminal urea group, wherein unit A is present in an amount of about 5 to about 50 mol % and has the formula is represented by wherein R1 is selected such that the homopolymer of A is alkali-soluble, unit B is present in an amount of about 20 to about 70 mol % and has the following formula is represented by wherein R2 is selected such that the homopolymer of B has a glass transition temperature greater than 100° C., preferably a glass transition temperature in the range from about 100 to about 380° C.