Abstract: Negative-working imageable elements are prepared with radiation-sensitive imageable layers that contain surface-modified silica particles such as fumed silica particles and sol-gel silica particles, that are present in an amount of from about 1 to about 40 weight %, have an average particle size of from about 1 to about 500 nm, have surface hydroxy groups, and have a carbon content of from about 0.5 to about 15 weight % that is derived from surface hydrophobic groups having 1 to 30 carbon atoms. The presence of the surface-modified silica particles provides improved abrasion resistance, reduced tackiness, and various other desired properties.

Abstract: Single- and multi-layer positive-working imageable elements include an ink receptive outer layer includes a primary polymeric binder that is a poly(vinyl phenol) or a phenolic polymer having certain acidic groups. The use of this type of polymeric binder makes the imaged elements developable in low pH (11 or less) alkaline developers.

Abstract: A computer-to-press multi-layer, positive-working imageable element has improved surface abrasion resistance from a micro-roughening of the outermost surface. This improvement is provided by spraying a solution consisting essentially of one or more dissolved organic resins in a solvent onto the outermost imageable layer of the imageable element. The one or more organic resins are soluble or dispersible in an aqueous alkaline solution and are present in the sprayed solution in an amount of at least 3 weight %. The sprayed solution is applied to deposit at least 10 mg/m2 and no more than 100 mg/m2 of the one or more dissolved organic resins onto the outermost imageable layer in the form of dots in a random pattern. The sprayed dots are then dried. The imageable elements can be imaged and developed to provide lithographic printing plates.

Abstract: A positive-working imageable element comprises inner and outer layers and an infrared radiation absorbing compound such as an IR absorbing dye. The ink receptive outer layer includes a phenolic polymeric binder that is soluble in a developer having a pH of from about 7 to about 11. The use of this type of polymeric binder reduces residue in the developer as elements are processed.

Abstract: Radiation-sensitive compositions and imageable elements include a polymeric or non-polymeric component in an imageable layer, which component includes 1H-tetrazole groups. The non-polymeric components can be radically polymerizable compounds. The polymeric components can have 1H-tetrazole groups that are pendant to the backbone. The use of such components in negative- or positive-working imageable elements provides high photospeed and improved developability for providing imaged and developed elements, such as lithographic printing plates that show improved chemical resistance and run length.

Abstract: Single- and multi-layer positive-working imageable elements include an ink receptive outer layer that includes inorganic, non-metallic, inert discrete particles, such as nano-sized silica, aluminum oxide, or titanium dioxide particles. The presence of these particles in the outermost layer improves the abrasion and scratch resistance of the elements.

Abstract: Single- and multi-layer positive-working imageable elements include an ink receptive outer layer includes a primary polymeric binder that is a poly(vinyl phenol) or a phenolic polymer having certain acidic groups. The use of this type of polymeric binder makes the imaged elements developable in low pH (11 or less) alkaline developers.

Abstract: A positive-working imageable element comprises inner and outer layers. The ink receptive outer layer includes a phenolic resin binder that is soluble in a developer having a pH greater than 11. Dissolution suppressing components for the phenolic resin binder are generally excluded from the outer layer or present at a very low amount.

Abstract: Thermally imagable elements are described comprising on a substrate with hydrophilic surface (a) a first layer comprising a first polymer soluble or swellable in aqueous alkaline developer and insoluble in organic solvents with low polarity and (b) a second layer comprising a second polymer soluble or swellable in aqueous alkaline developer, wherein the first polymer is different from the second polymer and the second polymer comprises vinyl acetal repeating units and pendant acidic groups selected from COOH, —SO3H, —PO3H2, —PO4H2, aromatic OH and groups having acidic amide or imide groups.

Abstract: A positive-working imageable element comprises inner and outer layers and an infrared radiation absorbing compound such as an IR absorbing dye. The ink receptive outer layer includes a phenolic polymeric binder that is soluble in a developer having a pH of from about 7 to about 11. The use of this type of polymeric binder reduces residue in the developer as elements are processed.

Abstract: The invention relates to a process for the production of a heat-sensitive imageable element comprising: (a) providing a substrate, (b) applying a first coating solution, comprising at least one photothermal conversion material, at least one polymer A soluble or swellable in an aqueous alkaline developer and at least one solvent, (c) drying, (d) applying a second coating solution, comprising at least one cross-linkable polyfunctional enolether, at least one polymer B comprising hydroxy groups and/or carboxy groups, and at least one solvent, wherein the polymer used in the first coating solution does not dissolve in this solvent, wherein the second coating solution does not contain a photothermal conversion material, and (e) drying at a temperature of at least 60° C.

Abstract: Radiation-sensitive negative working element comprising (a) a substrate with a hydrophilic surface and (b) a layer on the hydrophilic surface of the substrate, wherein said layer comprises a modified polymer obtainable by reacting (i) a polymer with —COOH, —SO3H, —P03H2 and/or —PO4H2 in the side chains, wherein the polymer is soluble in aqueous alkaline solutions and the solubility is not changed by IR radiation, and (ii) a salt with an inorganic or organic cation, wherein the modified polymer is soluble in aqueous alkaline solutions and the solubility is not changed by IR radiation, said layer being soluble in aqueous alkaline developer, but is rendered insoluble in aqueous alkaline developer by IR radiation.

Abstract: Developer composition obtainable by (a) providing water, (b) dissolving such an amount of an alkaline component selected from alkali silicates, alkali hydroxides, Na3PO4, K3PO4, NR4OH, wherein each R is independently selected from C1C4 alkyl groups and C1-C4 hydroxyalkyl groups, and mixtures thereof in the water provided in step (a) that a pH of more than 12 is obtained, and (c) dissolving a stabilizer selected from M2CO3, MHCO3, or a mixture of 2 or more thereof, wherein each M is independently selected from Li, Na, K and NR?4 and each R? independently represents H or C1-C4 alkyl, in the solution obtained in step (b) wherein the amount of the added stabilizer is such that the amount of the added carbonate anion is 1.5 to 20 wt-%, based on the total weight of the developer composition.

Abstract: Multilayer, positive working, thermally imageable, bakeable imageable elements have a substrate, an underlayer, and a top layer. The underlayer comprises a polymeric material that comprises, in polymerized form from about 5 mol % to about 30 mol % of recurring units derived from an ethylenically unsaturated polymerizable monomer having a carboxy group; from about 20 mol % to about 75 mol % of recurring units derived from N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; and from about 3 mol % to about 50 mol % of recurring units derived from a compound represented by the formula: CH2?C(R2)—C(O)—NH—CH2—OR1, in which R1 is C1 to C12 alkyl, phenyl, C1 to C12 substituted phenyl, C1 to C12 aralkyl, or Si(CH3)3; and R2 is hydrogen or methyl. Other materials, such as a resin or resins having activated methylol and/or activated alkylated methylol groups, such as a resole resin, may be present in the underlayer.

Abstract: A positive-working imageable element comprises inner and outer layers and an infrared radiation absorbing compound such as an IR absorbing dye. The inner layer includes a first polymeric material. The ink receptive outer layer includes a second polymeric binder comprising pendant carboxy groups that provides improved chemical resistance to the imageable element and reduced residue from development.

Abstract: Heat-sensitive element comprising (a) an optionally pre-treated substrate (b) a positive working heat-sensitive coating comprising (i) at least one novolak resin, (ii) at least one component which reduces the aqueous alkaline developer solubility of novolak, wherein said reduction in solubility is reversed upon the application of heat, and (iii) at least one acidic polyvinyl acetal comprising the structural units (A), (B), (C) (A) (B) (C) and (D) wherein (D) is at least one unit selected from (D-1), (D-2), and (D-3): (D-1) (D-2) (D-3) wherein R1 is a hydrogen atom or a C1-C4 alkyl group, R2 is a hydrogen atom or a C1-C18 alkyl group, R3 is a hydrogen atom or a C1-C4 alkyl group, R4 is a hydrogen atom or a C1-C4 alkyl group, R5 is —COOH, —(CH2)a—COOH, —O—(CH2)a—COOH, —SO3H, —PO3H2 or —PO4H2, a is an integer from 1 to 8, and X is selected from —(CR6R7)n— and —CR8?CR9— wherein n is an integer of 1 to 6, each R6 and R7 is independently selected from a hydrogen atom and C1-C6 alkyl group, and R8 and R9 are indepen

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, bakeable imageable elements have a substrate, an underlayer, and a top layer. The underlayer comprises a polymeric material that comprises, in polymerized form from about 5 mol % to about 30 mol % of recurring units derived from an ethylenically unsaturated polymerizable monomer having a carboxy group; from about 20 mol % to about 75 mol % of recurring units derived from N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; and from about 3 mol % to about 50 mol % of recurring units derived from a compound represented by the formula: CH2?C(R2)—C(O)—NH—CH2—OR1, in which R1 is C1 to C12 alkyl, phenyl, C1 to C12 substituted phenyl, C1 to C12 aralkyl, or Si(CH3)3; and R2 is hydrogen or methyl. Other materials, such as a resin or resins having activated methylol and/or activated alkylated methylol groups, such as a resole resin, may be present in the underlayer.

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: Imageable elements useful in lithographic printing, and processes for their use, are disclosed. The elements comprise a hydrophilic substrate, an imageable layer over the substrate, and a thermally activated crosslinking agent. The imageable layer comprises a polymeric material that comprises one or more functional groups selected from the group consisting of carboxyl, carboxylic acid anhydride, phenolic hydroxyl, and sulphonamide. A preferred crosslinking group is the oxazoline group. The element is heated after exposure and development to crosslink a polymeric material.