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: A negative-working imageable element includes a combination of a specific polymeric binder comprising pendant allyl ester groups with an highly efficient iodonium borate free radical initiator to provide solvent resistance, excellent digital imaging speed (sensitivity) and can be imaged and developed without a preheat step to provide lithographic printing plates. The polymeric binder can be prepared with a precursor polymer having pendant carboxy groups that are converted to allyl ester groups using an allyl-containing halide in the presence of a base in order to avoid gelation. The desired iodonium borates are diaryliodonium borates having substituents on the aryl rings.

Abstract: A radiation-sensitive composition and negative-working imageable element includes a polymeric binder comprising pendant allyl ester groups to provide solvent resistance, excellent digital speed (sensitivity) and can be imaged and developed without a preheat step to provide lithographic printing plates. The polymeric binder can be prepared with a precursor polymer having pendant carboxy groups that are converted to allyl ester groups using an allyl-containing halide in the presence of a base in order to avoid gelation.

Abstract: A radiation-sensitive composition and negative-working imageable element includes a polymeric binder comprising pendant allyl ester groups to provide solvent resistance, excellent digital speed (sensitivity) and can be imaged and developed without a preheat step to provide lithographic printing plates. The polymeric binder can be prepared with a precursor polymer having pendant carboxy groups that are converted to allyl ester groups using an allyl-containing halide in the presence of a base in order to avoid gelation.

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: A radiation-sensitive composition includes a radically polymerizable component and an iodonium borate initiator composition capable of generating radicals sufficient to initiate polymerization of the free radically polymerizable component upon exposure to imaging radiation. The iodonium borate composition includes a particular diaryliodonium borate compound having organic substituents to provide a sum of at least 6 carbon atoms on the iodonium cation phenyl rings. This composition can be applied to a suitable substrate to provide a negative-working imageable element with improved digital speed and good shelf life and that can be imaged to provide lithographic printing plates. The imaged elements can be developed either on-press or off-press using alkaline developers.

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 combination of two different polymeric binders one of which has an acid number of at least 30, which combination of polymers provides improved post-development bakeability (more quickly baked or cured at lower temperatures) and desired digital speed with no loss in chemical resistance.

Abstract: A radiation-sensitive composition includes a radically polymerizable component and a borate initiator composition capable of generating radicals sufficient to initiate polymerization of the radically polymerizable component upon exposure to imaging radiation. This composition also includes a radiation absorbing compound (such as an IR-sensitive dye), a polymeric binder comprising a polymer backbone to which is directly or indirectly linked a pendant group comprising a reactive vinyl group, and a primary additive that is a poly(alkylene glycol) or an ether or ester thereof that has a number average molecular weight of from about 200 and up to 4000 and comprises from about 2 to about 50 weight % based on the total composition solids content. This composition can be used to prepare a negative-working imageable element that can be imaged at relatively low energy and developed without a preheat step.

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. When the imageable element is imaged and developed, the resulting printing plate may exhibit improved on-press solvent resistance and longer press life.

Abstract: A radiation-sensitive composition includes a radically polymerizable component and a borate initiator composition capable of generating radicals sufficient to initiate polymerization of the radically polymerizable component upon exposure to imaging radiation. This composition also includes a radiation absorbing compound (such as an IR-sensitive dye), a polymeric binder comprising a polymer backbone to which is directly or indirectly linked a pendant group comprising a reactive vinyl group, and a primary additive that is a poly(alkylene glycol) or an ether or ester thereof that has a number average molecular weight of from about 200 and up to 4000 and comprises from about 2 to about 50 weight % based on the total composition solids content. This composition can be used to prepare a negative-working imageable element that can be imaged at relatively low energy and developed without a preheat step.

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: 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: 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: 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: A negative-working radiation-sensitive composition includes a polymeric binder comprising a polymer backbone and having attached thereto a carbazole derivative represented by the following Structure (I): wherein Y is a direct bond or a linking group, and R1 to R8 are independently hydrogen, or an alkyl, alkenyl, aryl, halo, cyano, alkoxy, acyl, acyloxy, or carboxylate groups, or any adjacent R1 through R8 groups can together form a carbocyclic or heterocyclic group or a fused aromatic ring. The composition can be sensitive to radiation having a maximum wavelength of from about 150 to about 1500 nm, and can be used to prepare negative-working imageable elements that be imaged and developed as lithographic printing plates.

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 convenient and economical method for preparing infrared absorbing cyanine dyes useful in lithographic printing plate precursors is disclosed. The reaction is generally carried out by condensation of a heterocyclic base containing an activated methylene group and an unsaturated bisaldehyde or its equivalent in a solvent or solvent mixture at about 20–150° C. All the reactions necessary for production of the infrared absorbing cyanine dye may be carried out in one reaction vessel without isolating any intermediate products.

Abstract: Imageable elements with improved dot stability are disclosed. The imageable elements comprise a layer of an imageable composition over a support. The imageable composition comprises an infrared absorbing compound, an acid generator, an acid activatable crosslinking agent, a polymeric binder, and about 0.01 wt % to 1 wt % of an added onium compound. The elements may be thermally imaged and developed to produce images useful as lithographic printing plates.

Abstract: Substrates for lithographic printing plate precursors and lithographic printing plate precursors are disclosed. The substrates comprise an aluminum or aluminum alloy support and the a layer of interlayer material on the support. The interlayer material is a co-polymer that comprise (1) acid groups and/or phosphonic acid groups, and (2) silyl groups substituted with three alkoxy and/or phenoxy groups. The lithographic printing plate precursors additionally comprise an imageable layer over the interlayer.

Abstract: Infrared absorbing compounds are disclosed. The compounds are co-polymers that comprise covalently attached ammonium, sulfonium, phosphonium, and/or iodonium cations, and infrared absorbing cyanine anions that have two to four sulfonate groups and/or sulfate groups, and/or infrared absorbing oxonol anions. The infrared absorbing compounds can be used in aqueous developable lithographic printing plate precursors.