Abstract: Lithographic printing plates are formed by imagewise exposing a single-layer or dual-layer positive-working lithographic printing plate precursor. The precursor has an outermost ink receptive layer containing a phenolic resin. The exposed precursor can be processed using a silicate-free developer composition having a pH of at least 12.5. This composition also includes an alkali metal hydroxide; a coating protecting agent that is a quaternary ammonium salt or phosphonium salt, or a mixture thereof, and a moderator for the coating protecting agent that is represented by the following general formula (I): wherein m is at an integer of at least 1 and up to and including 10 and M represents one or more counterions sufficient to balance the negatively-charged sulfonate groups.

Abstract: Lithographic printing plates are formed by imagewise exposing a single-layer or dual-layer positive-working lithographic printing plate precursor. The precursor has an outermost ink receptive layer containing a phenolic resin. The exposed precursor can be processed using a silicate-free developer composition having a pH of at least 12.5. This composition also includes an alkali metal hydroxide; a coating protecting agent that is a quaternary ammonium salt or phosphonium salt, or a mixture thereof, and a moderator for the coating protecting agent that is represented by the following general formula (I): wherein m is at an integer of at least 1 and up to and including 10 and M represents one or more counterions sufficient to balance the negatively-charged sulfonate groups.

Abstract: A negative-working, infrared radiation-sensitive lithographic printing plate precursor is prepared to contain an infrared radiation-sensitive imageable layer that is disposed on the hydrophilic surface of a substrate. This imageable layer contains sufficient free radical chemistry for infrared sensitivity and imaging to polymerize the exposed regions. This chemistry is dispersed within a primary polymeric binder comprising polyalkylenes oxide segments and optional pendant cyano groups and is present in the form of particles, and a secondary crosslinked hydrophobic binder to provide improved ink receptivity, rapid development, and run length especially with aged precursors. Exposed precursors can be developed on-press while forming the first printed impressions.

Abstract: A thermally-sensitive, positive-working lithographic printing plate precursor can be used to prepare lithographic printing plates using high pH, silicate-free processing solutions. The precursor has a grained an anodized aluminum-containing substrate including a poly(vinyl phosphonic acid) interlayer. A first ink receptive layer, and optionally a second ink receptive layer, is disposed directly on the poly(vinyl phosphonic acid) interlayer. This first ink receptive layer comprises an aromatic acid dye that comprises at least two aromatic groups in an amount of least 0.5 weight %. In addition, the precursor comprises an infrared radiation absorber in one of the layers.

Abstract: Lithographic printing plate are formed by imagewise exposing a positive-working lithographic printing plate precursor with infrared radiation to form an imaged precursor comprising exposed regions and non-exposed regions, and processing the imaged precursor to remove the exposed regions using a processing solution having a pH of 12 or more, that contains a metal cation M2+ selected from barium, calcium, strontium, and zinc cations, and is substantially silicate-free. The positive-working lithographic printing plate precursor comprises a grained and anodized aluminum-containing substrate, a first ink receptive layer comprising at least one water-insoluble, alkali solution-soluble or -dispersible first resin, a second ink receptive layer disposed over the first receptive layer, and an infrared radiation absorber in an amount of at least 0.5 weight %, in either or both of the first ink receptive layer and the second ink receptive layer.

Abstract: Electrochemically grained and anodized aluminum supports are treated with a post-treatment coating solution containing a polymer derived at least in part from vinyl phosphonic acid and phosphoric acid. This post-treated support is useful as substrates in the preparation of lithographic printing plate precursors. The post-treatment substrate treatment enables wide latitude in manufacturing and compatibility with silicate-free developers to achieve negligible background staining and oxide attack.

Abstract: Lithographic printing plate are formed by imagewise exposing a positive-working lithographic printing plate precursor with infrared radiation to form an imaged precursor comprising exposed regions and non-exposed regions, and processing the imaged precursor to remove the exposed regions using a processing solution having a pH of 12 or more, that contains a metal cation M2+ selected from barium, calcium, strontium, and zinc cations, and is substantially silicate-free. The positive-working lithographic printing plate precursor comprises a grained and anodized aluminum-containing substrate, a first ink receptive layer comprising at least one water-insoluble, alkali solution-soluble or -dispersible first resin, a second ink receptive layer disposed over the first receptive layer, and an infrared radiation absorber in an amount of at least 0.5 weight %, in either or both of the first ink receptive layer and the second ink receptive layer.

Abstract: Positive-working lithographic printing plate precursors have an inner layer that includes a polymeric binder having an acid number of at least 30 mg KOH/g of polymer to and including 150 mg KOH/g of polymer, at least 3 weight % of recurring units derived from one or more N-alkoxymethyl(alkyl)acrylamides or alkoxymethyl(alkyl)acrylates, at least 2 weight % of recurring units having pendant 1H-tetrazole groups, and at least 10 weight % of recurring units having pendant cyano groups. The use of such polymeric binders in the inner layer provides good bakeability and chemical solvent resistance. Such positive-working lithographic printing plate precursors also include an outer layer disposed over the inner layer, which outer layer comprises an infrared radiation absorbing compound.

Abstract: Positive-working lithographic printing plate precursors have an inner layer that includes a polymeric binder having an acid number of at least 30 mg KOH/g of polymer to and including 150 mg KOH/g of polymer, at least 3 weight % of recurring units derived from one or more N-alkoxymethyl(alkyl)acrylamides or alkoxymethyl(alkyl)acrylates, at least 2 weight % of recurring units having pendant 1H-tetrazole groups, and at least 10 weight % of recurring units having pendant cyano groups. The use of such polymeric binders in the inner layer provides good bakeability and chemical solvent resistance. Such positive-working lithographic printing plate precursors also include an outer layer disposed over the inner layer, which outer layer comprises an infrared radiation absorbing compound.

Abstract: A thermally-sensitive, positive-working lithographic printing plate precursor can be used to prepare lithographic printing plates using high pH, silicate-free processing solutions. The precursor has a grained an anodized aluminum-containing substrate including a poly(vinyl phosphonic acid) interlayer. A first ink receptive layer, and optionally a second ink receptive layer, is disposed directly on the poly(vinyl phosphonic acid) interlayer. This first ink receptive layer comprises an aromatic acid dye that comprises at least two aromatic groups in an amount of least 0.5 weight %. In addition, the precursor comprises an infrared radiation absorber in one of the layers.

Abstract: A negative-working lithographic printing plate precursor is used for making lithographic printing plates from infrared radiation imaging. The precursor comprises free radical chemistry and a specific infrared radiation absorber that is a cyanine dye and defined by Formula (1a) described in the disclosure. This particular infrared radiation absorber provides both IR sensitivity and print out after imaging.

Abstract: On-press developable, negative-working, infrared radiation-sensitive lithographic printing plate precursors have an imageable layer on a substrate. The imageable layer includes a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to infrared radiation, a polymeric binder, a first infrared radiation absorbing compound that has a tetraaryl pentadiene chromophore, and a second infrared radiation absorbing compound that is different than the first infrared radiation absorbing compound. The first IR absorbing compound absorbs in both the IR and visible regions of the electromagnetic spectrum and provides coloration for visual inspection of the lithographic printing plates.

Abstract: A lithographic processing solution has a pH of less than 12 and comprises at least 0.001 and up to and including 1 weight % of a water-soluble or water-dispersible, non-IR-sensitive compound that has a heterocyclic moiety with a quaternary nitrogen in the 1-position of the heterocyclic ring, and has one or more electron donating substituents attached to the heterocyclic ring, at least one of which electron donating substituents is attached in the 2-position. This processing solution can be used to develop both single-layer and multi-layer positive-working lithographic printing plate precursors that have been imaged using infrared radiation.

Abstract: A thermally-sensitive, positive-working lithographic printing plate precursor can be used to prepare lithographic printing plates using high pH, silicate-free processing solutions. The precursor has a grained an anodized aluminum-containing substrate including a poly(vinyl phosphonic acid) interlayer. A first ink receptive layer, and optionally a second ink receptive layer, is disposed directly on the poly(vinyl phosphonic acid) interlayer. This first ink receptive layer comprises an aromatic acid dye that comprises at least two aromatic groups in an amount of least 0.5 weight %. In addition, the precursor comprises an infrared radiation absorber in one of the layers.

Abstract: Positive-working lithographic printing plate precursors have an inner layer that includes a polymeric binder having an acid number of at least 30 mg KOH/g of polymer to and including 150 mg KOH/g of polymer, at least 3 weight % of recurring units derived from one or more N-alkoxymethyl(alkyl)acrylamides or alkoxymethyl(alkyl)acrylates, at least 2 weight % of recurring units having pendant 1H-tetrazole groups, and at least 10 weight % of recurring units having pendant cyano groups. The use of such polymeric binders in the inner layer provides good bakeability and chemical solvent resistance. Such positive-working lithographic printing plate precursors also include an outer layer disposed over the inner layer, which outer layer comprises an infrared radiation absorbing compound.

Abstract: A negative-working lithographic printing plate precursor is used for making lithographic printing plates from infrared radiation imaging. The precursor comprises free radical chemistry and a specific infrared radiation absorber that is a cyanine dye and defined by Formula (1a) described in the disclosure. This particular infrared radiation absorber provides both IR sensitivity and print out after imaging.

Abstract: A thermally-sensitive, positive-working lithographic printing plate precursor can be used to prepare lithographic printing plates using high pH, silicate-free processing solutions. The precursor has a grained an anodized aluminum-containing substrate including a poly(vinyl phosphonic acid) interlayer. A first ink receptive layer, and optionally a second ink receptive layer, is disposed directly on the poly(vinyl phosphonic acid) interlayer. This first ink receptive layer comprises an aromatic acid dye that comprises at least two aromatic groups in an amount of least 0.5 weight %. In addition, the precursor comprises an infrared radiation absorber in one of the layers.

Abstract: Electrochemically grained and anodized aluminum supports are treated with a post-treatment coating solution containing a polymer derived at least in part from vinyl phosphonic acid and phosphoric acid. This post-treated support is useful as substrates in the preparation of lithographic printing plate precursors. The post-treatment substrate treatment enables wide latitude in manufacturing and compatibility with silicate-free developers to achieve negligible background staining and oxide attack.

Abstract: Electrochemically grained and anodized aluminum supports are treated with a post-treatment coating solution containing a polymer derived at least in part from vinyl phosphonic acid and phosphoric acid. This post-treated support is useful as substrates in the preparation of lithographic printing plate precursors. The post-treatment substrate treatment enables wide latitude in manufacturing and compatibility with silicate-free developers to achieve negligible background staining and oxide attack.

Abstract: A positive-working multi-layer lithographic printing plate precursor has an inner imageable layer disposed over a substrate. This inner imageable layer comprises one or more first polymeric binders that are present in a total amount of at least 50 weight % and up to and including 97 weight %, based on total inner imageable layer dry weight. The precursor also has an ink-receptive outer imageable layer disposed over the inner imageable layer and this ink-receptive outer imageable layer comprises one or more second polymeric binders that are different than the first polymeric binder. Each of the one or more first polymeric binders has a weight average molecular weight of at least 200,000 and can also have a polydispersity of at least 4.