Abstract: An imaged and developed element, such as a lithographic printing plate, is provided by infrared radiation imaging of a negative-working imageable element having an outermost imageable layer that includes a free radically polymerizable component, a free radical initiator composition comprising a diaryliodonium borate, and an infrared radiation absorbing compound. The imageable layer also includes a polymeric binder that is represented by the following Structure (I): -(A)w-(A?)w?-??(I) wherein A represents recurring units comprising a pendant reactive vinyl group, A? represents recurring units other than those represented by A, w is from about 1 to about 70 mol %, and w? is from about 30 to about 99 mol %. The imagewise exposed element is developed with a gum to remove only the non-exposed regions. The gum has a pH greater than 7 and up to about 11 and at least 1 weight % of an anionic surfactant.

Abstract: A negative-working imageable element has an imageable layer that includes an initiator composition including an iodonium cation and a boron-containing anion at a molar ratio of at least 1.2:1, an infrared radiation absorbing compound, a primary polymeric binder, and a spirolactone or spirolactam colorant precursor. The imaged element exhibits improved print-out.

Abstract: A negative-working imageable element has an imageable layer that includes an initiator composition including an iodonium cation and a borate anion, an infrared radiation absorbing compound, a particulate primary polymeric binder, and a phosphate (meth)acrylate adhesion promoter. The element also includes a polymeric overcoat disposed over the imageable layer and can be developed on-press to provide a lithographic printing plate with high run length. The element also has improved shelf-life.

Abstract: Negative-working imageable elements that can be imaged using infrared radiation comprise an imageable layer and a protective overcoat on a hydrophilic substrate. The imageable layer includes an IR-sensitive cyanine dye. The protective overcoat predominantly comprises one or more poly(vinyl alcohol) resins, each of which has a hydrolysis level of 85% or less. The use of this particular overcoat composition used in combination with the IR-sensitive cyanine dye provides improved tolerance to fogging by white light while maintaining desired imaging speed.

Abstract: A radiating-sensitive composition and negative-working imageable element includes a free radically polymerizable component, an initiator composition capable of generating radicals sufficient to initiate polymerization of the free radically polymerizable component upon exposure to imaging radiation, a radiation absorbing compound, and particles of a poly(urethane-acrylic) hybrid that are distributed throughout the composition forming an imageable layer in the element. Imaging can be accomplished at a wide range of wavelengths from about 150 to about 1500 nm, and development can be accomplished using an organic solvent-based developer, warm water, plate cleaner, or on-press using a combination of a lithographic printing ink and a fountain solution.

Abstract: A radiation-sensitive composition includes an initiator composition, a radiation absorbing compound, and a particulate primary polymeric binder that has a backbone comprising multiple urethane moieties and further comprises side chains comprising free radically polymerizable groups attached to the backbone. This primary polymeric binder can be used in place of or in addition to a conventional free radically polymerizable component. This composition can be used to provide negative-working imageable elements that can be imaged and developed to provide lithographic printing plates.

Abstract: A radiation-sensitive composition and negative-working imageable element includes a free radically polymerizable component, an initiator composition capable of generating radicals sufficient to initiate polymerization of the free radically polymerizable component upon exposure to imaging radiation, a radiation absorbing compound, and particles of a poly(urethane-acrylic) hybrid that are distributed throughout the composition forming an imageable layer in the element. Imaging can be accomplished at a wide range of wavelengths from about 150 to about 1500 nm, and development can be accomplished using an organic solvent-based developer, warm water, plate cleaner, or on-press using a combination of a lithographic printing ink and a fountain solution.

Abstract: Positive-working imageable elements comprise a radiation absorbing compound and inner and outer layers on a substrate having a hydrophilic surface. The inner layer comprises a polymeric material that is removable using an alkaline developer and comprises a backbone and attached groups represented by the following Structure Q: wherein L1, L2, and L3 independently represent linking groups, T1, T2, and T3 independently represent terminal groups, and a, b, and c are independently 0 or 1. The imageable elements have improved resistance to development and printing chemicals and solvents.

Abstract: Negative-working imageable elements can be imaged and then developed using a lower pH organic-based single-phase developer that is less toxic and corrosive and that can be more readily disposed of after use. This developer has a pH less than 12 and comprises a) an amphoteric surfactant comprising a nitrogen-containing heterocycle, b) an amphoteric surfactant having two or more nitrogen atoms, or c) an amphoteric surfactant of a) and an amphoteric surfactant of b).

Abstract: Both single-layer and multi-layer positive-working imageable compositions can be used in positive-working elements having a substrate and at least one imageable layer. These elements can be used to prepare lithographic printing plates. The imageable elements include a radiation absorbing compound and a hydroxystyrene polymer having repeating branched hydroxystyrene units.

Abstract: Thermally imageable multilayer imageable elements useful as lithographic printing plate precursors that have good solvent resistance are disclosed. The underlayer of the imageable element comprises an acidic copolymer that comprises, in polymerized form, about 10 mol % to about 75 mol % of one or more monomers of the formula: CH2?CH(R1)-Z-X—NH—CO—NH—C6H3—(R2)(CO2H); in which: R1 is H or CH3; R2 is H or OH; Z is —C6H4— or —C(O) —Y—; Y is —O— or —NH—; and X is selected from —C(CH3)2—, —CH(CH3)— and —(CH2)n—, in which n is an integer from 1 to 12.

Abstract: Both single-layer and multilayer imageable elements have a substrate and at least one imageable layer. The elements can be used to prepare either negative- or positive-working imaged elements, for example as lithographic printing plates. The imageable elements also include a radiation absorbing compound and a solvent-resistant polymer comprising pendant phosphoric acid groups, pendant adamantyl groups, or both. When this polymer comprises pendant adamantyl groups, they are connected to the polymer backbone through a urea or urethane group. The imageable elements have improved chemical resistance and thermal bakeability from the presence of the unique solvent-resistant polymer.

Abstract: Single-layer and multilayer imageable elements have a substrate and at least one imageable layer and can be used to prepare positive-working lithographic printing plates. The imageable elements also include a radiation absorbing compound and a solvent-resistant polymer binder comprising an —N(R)—C(?X)—N(R?)—S(?O)2— moiety that is attached to the polymer backbone, wherein X is O or S, R and R? are independently hydrogen, halo, or an alkyl group having 1 to 6 carbon atoms. This solvent-resistant polymer binder is located in the imageable layer closest to the substrate and provides improved chemical resistance.

Abstract: The present invention provides methods of imagewise exposing a thermally sensitive composition formed from a nanopaste comprising inorganic nanoparticles, a carrier, and preferably certain polymeric binders. The composition has been applied to a substrate and treated to improve adhesion. Exposure affects the solubility of exposed portions of the applied and treated layer relative to unexposed portions of the applied layer. The imaged layer is then developed on-press with a fountain solution, lithographic ink, or both, to remove the exposed portions or unexposed portions of the layer to form an image in a printing plate.

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: Positive-working imageable elements are prepared by providing a first layer and second layers onto a substrate. Both layers include the same or different radiation absorbing compounds dispersed within different polymeric binders. After both layers are dried, they are heat treated at from about 40 to about 90° C. for at least 4 hours under conditions that inhibit the removal of moisture from the dried first and second layers. This method of preparation provides elements with improved imaging speed and good shelf life.

Abstract: A method of preparing negative-working, single-layer imageable elements improves their storage stability in a humid environment. The method includes enclosing the coated imageable elements in a water-impermeable sheet material that substantially inhibits the transfer of moisture to and from the imageable element. Such imageable elements include a radiation-sensitive composition that includes a radically polymerizable component, an initiator composition to provide radicals upon exposure to imaging radiation, a radiation absorbing compound, and a polymeric binder having poly(alkylene glycol) side chains.

Abstract: The present invention provides an imageable element including a lithographic substrate and an imageable layer disposed on the substrate. The imageable layer includes a radically polymerizable component, an initiator system capable of generating radicals sufficient to initiate a polymerization reaction upon exposure to imaging radiation, and a polymeric binder having a hydrophobic backbone and including both constitutional units having a pendant cyano group attached directly to the hydrophobic backbone, and constitutional units having a pendant group including a hydrophilic poly(alkylene oxide) segment. The invention also provides a method for preparing a suitable polymeric binder. The method comprises contacting a combination of co-monomers in a solvent mixture consisting essentially of a (C1–C6) alkanol and water.

Abstract: A positive-working imageable element comprises inner and outer layers and a radiation absorbing compound such as an IR absorbing dye. The inner layer includes a polymeric material that is removable using an alkaline developer. An ink receptive outer layer is not removable using an alkaline developer before its exposure to imaging radiation. The outer layer includes a polymer binder having pendant epoxy groups that are substantially unreacted during exposure.

Abstract: Positive-working imageable elements comprise a radiation absorbing compound and inner and outer layers on a substrate having a hydrophilic surface. The inner layer comprises a polymer that is removable using an alkaline developer and in which from about 1 to about 50 mol % of its recurring units are derived from one or more of the ethylenically unsaturated polymerizable monomers represented by the following Structure (I): CH2?C(R1)C(?O)NR2(CR3R4)nOH ??(I) wherein R1, R2, R3, and R4 are independently hydrogen, lower alkyl, or phenyl, and n is 1 to 20. The imageable elements having improved resistance to development and printing chemicals and solvents.