Abstract: Negative-working imageable elements can be imaged and processed to provide lithographic printing plates, especially with sulfuric acid-anodized aluminum substrates. These elements have an imageable outermost layer that contains two different polymeric binders, a primary polymeric binder is optionally present a discrete particles, and a secondary polymeric binder comprising a poly(vinyl acetate) that has a degree of hydrolysis of less than 60 mol %. These imageable elements can be designed for either off-press or on-press development.

Abstract: Negative-working imageable elements have an imageable layer comprising 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, one or more polymeric binders, and at least 5 weight % of core-shell particles comprising a hydrophobic polymeric core and a hydrophilic polymeric shell that is covalently bound to the polymeric core. The hydrophilic polymeric shell has one or more zwitterionic functional groups. These elements can be imaged such as by IR lasers to provide lithographic printing plates.

Abstract: Single- and multi-layer positive-working imageable elements include a first polymeric binder that is soluble in an alkaline developer upon exposure to imaging radiation and a radiation absorbing compound. The first polymeric binder comprises a backbone to which are attached pendant groups represented by the following Structure (I): wherein R1 and R2 are independently hydrogen or alkyl groups having 1 to 8 carbon atoms or aryl groups having 6 or 10 carbon atoms in the carbocyclic ring, L is a direct bond or a linking group having at least 1 carbon atom and optionally one or more nitrogen, oxygen, and sulfur atoms in the linking chain, and X is oxy, thio, or —NR— wherein R is hydrogen or an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 or 10 carbon atoms in the carbocyclic ring.

Abstract: A substrate useful for forming lithographic printing plate precursors includes a metal or polymer support and an interlayer comprising a trialkoxysilyl polyethylene glycol acrylate having the following Structure (I): wherein R1 and R2 are independently hydrogen or C1 to C6 alkyl, C1 to C6 alkenyl, C1 to C6 alkoxy, C1 to C6 acyl, C1 to C6 acyloxy, phenyl, halo, or cyano groups, or R1 and R2 together can form a cyclic group, R3 is hydrogen, or a C1 to C6 alkyl, phenyl, halo, or cyano group, R4 and R5 are independently hydrogen or methyl groups, R6 is hydrogen or a C1 to C12 alkyl group, X1 is —O— or —NR— wherein R is hydrogen or an alkyl or aryl group, X2 is —NR?— wherein R? is hydrogen or an alkyl or aryl group, m is an integer of from 15 to 200, and n is an integer of from 1 to 12. The lithographic printing plates can be negative-working and particularly useful for on-press development and have a sulfuric acid-anodized aluminum support.

Abstract: A method for providing a lithographic printing plate includes developing an exposed imageable element with an alkali silicate-containing developer composition having a pH of at least 12.0. The developer composition is regenerated by adding to it an alkali silicate-containing regenerator composition having a pH of at least 12.0. Conductivity of both the developer and regenerator compositions is suppressed from the presence of one or more conductivity reducing agents (such as glycerin). This conductivity suppression in the developer composition is greater than the suppression of the conductivity of the regenerator composition.

Abstract: Negative-working, on-press developable imageable element have improved shelf life and press run length because they include a free radically polymerizable composition comprising two or more ethylenically unsaturated compounds, each of which has two or more terminal acrylate groups, provided at least one of the ethylenically unsaturated compounds further comprises alkylene glycol units. In addition, the molar ratio of terminal acrylate groups to the alkylene glycol units in the non-polymeric free radically polymerizable composition is from about 1.25:1 to about 3:1.

Abstract: An imaged and developed element, such as a lithographic printing plate, is provided by infrared radiation imaging of a negative-working imagable element having an outermost imagable layer that includes a free radically polymerizable component, a free radical initiator composition comprising a diaryliodonium borate, and an infrared radiation absorbing compound. The imagable 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: Negative-working imageable elements can be imaged and processed to provide lithographic printing plates, especially with sulfuric acid-anodized aluminum substrates. These elements have an imageable outermost layer that contains two different polymeric binders, a primary polymeric binder is optionally present a discrete particles, and a secondary polymeric binder comprising a poly(vinyl acetate) that has a degree of hydrolysis of less than 60 mol %. These imageable elements can be designed for either off-press or on-press development.

Abstract: A substrate useful for forming lithographic printing plate precursors includes a metal or polymer support and an interlayer comprising a trialkoxysilyl polyethylene glycol acrylate having the following Structure (I): wherein R1 and R2 are independently hydrogen or C1 to C6 alkyl, C1 to C6 alkenyl, C1 to C6 alkoxy, C1 to C6 acyl, C1 to C6 acyloxy, phenyl, halo, or cyano groups, or R1 and R2 together can form a cyclic group, R3 is hydrogen, or a C1 to C6 alkyl, phenyl, halo, or cyano group, R4 and R5 are independently hydrogen or methyl groups, R6 is hydrogen or a C1 to C12 alkyl group, X1 is —O— or —NR— wherein R is hydrogen or an alkyl or aryl group, X2 is —NR?— wherein R? is hydrogen or an alkyl or aryl group, m is an integer of from 15 to 200, and n is an integer of from 1 to 12. The lithographic printing plates can be negative-working and particularly useful for on-press development and have a sulfuric acid-anodized aluminum support.

Abstract: A negative-working imagable composition and element includes an initiator composition, an infrared radiation absorbing compound, a polymeric binder, and a stabilizing composition. The imaged element can be developed on-press and exhibits improved shelf-life under high humidity conditions. The stabilizing composition comprising at least one compound represented by Structure (ST-I) and at least one compound represented by Structure (ST-II): wherein m is 1 or 2, n is 1 to 50, R is hydrogen when m is 1, R1 through R3 are independently hydrogen or methyl, and L is an aliphatic, carbocyclic, heterocyclic, heteroatom divalent linking group, or a combination thereof.

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 a free radically polymerizable component, a free radical initiator composition, an infrared radiation absorbing compound, and adhesion promoter that is an organic compound having an ethylenically unsaturated carbon-carbon double bond that is connected to an alkoxysilyl or hydroxysilyl group. The use of the adhesion promoter provides increased printing durability for the imaged and developed element, especially those having sulfuric acid-anodized aluminum substrates.

Abstract: Single- and multi-layer positive-working imageable elements include a first polymeric binder that is soluble in an alkaline developer upon exposure to imaging radiation and a radiation absorbing compound. The first polymeric binder comprises a backbone to which are attached pendant groups represented by the following Structure (I): wherein R1 and R2 are independently hydrogen or alkyl groups having 1 to 8 carbon atoms or aryl groups having 6 or 10 carbon atoms in the carbocyclic ring, L is a direct bond or a linking group having at least 1 carbon atom and optionally one or more nitrogen, oxygen, and sulfur atoms in the linking chain, and X is oxy, thio, or —NR— wherein R is hydrogen or an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 or 10 carbon atoms in the carbocyclic ring.

Abstract: An imaged and developed element, such as a lithographic printing plate, is provided by violet radiation imaging of a negative-working imageable element having an outermost imageable layer that includes a free radically polymerizable component, an initiator composition that provides free radicals upon violet irradiation, a sensitizer, and a polymeric binder having pendant reactive vinyl groups. The element also includes an additive that is represented by the following Structure (II): wherein R1, R2, R3, and R4 are independently hydrogen, or alkyl, alkenyl, cycloalkyl, or aryl groups. The imaged element can be developed using a gum having a pH greater than 6 and up to about 11 and comprising at least 1 weight % of one or more anionic surfactants.

Abstract: A negative-working imageable composition and element includes an initiator composition, an infrared radiation absorbing compound, a polymeric binder, and a stabilizing composition. The imaged element can be developed on-press and exhibits improved shelf-life under high humidity conditions. The stabilizing composition comprising at least one compound represented by Structure (ST-I) and at least one compound represented by Structure (ST-II): wherein m is 1 or 2, n is 1 to 50, R is hydrogen when m is 1, R1 through R3 are independently hydrogen or methyl, and L is an aliphatic, carbocyclic, heterocyclic, heteroatom divalent linking group, or a combination thereof.

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 method for providing a lithographic printing plate includes developing an exposed imageable element with an alkali silicate-containing developer composition having a pH of at least 12.0. The developer composition is regenerated by adding to it an alkali silicate-containing regenerator composition having a pH of at least 12.0. Conductivity of both the developer and regenerator compositions is suppressed from the presence of one or more conductivity reducing agents (such as glycerin). This conductivity suppression in the developer composition is greater than the suppression of the conductivity of the regenerator composition.

Abstract: A highly alkaline developer composition includes an alkali silicate, an alkyl sulfate, and a water-soluble or water-dispersible polyhydroxy compound such as glycerin. The developer composition is useful for processing imaged elements to produce lithographic printing plates with reduced etching of the aluminum substrates that have been coated with hydrophilic polymers such as poly(vinyl phosphonic acid) and with minimal sludging in the developer tank.