Abstract: A laser sensitive lithographic printing plate comprises an electrochemically grained, anodized, hydrophilically treated aluminum substrate with a reflection optical density of 0.30 or higher; a free radical polymerizable photosensitive layer; and a water soluble or dispersible overcoat. The photosensitive layer comprises a polymeric binder, a free radical polymerizable monomer, a free radical initiator, and a sensitizing dye. Such dark aluminum substrate in combination with the hydrophilic treatment allows both clean background and good printing durability. Such plate can be exposed with a suitable laser at lower dosage to cause hardening in the exposed areas. The exposed plate can be developed with a regular liquid developer or with ink and/or fountain solution.

Abstract: High speed violet or ultraviolet laser sensitive lithographic printing plate comprising on a hydrophilic substrate a specific photosensitive composition is described. The photosensitive layer comprises an alkaline soluble polymeric binder, a multifunctional (meth)acrylate monomer, a free-radical initiator, and a sensitizing dye. The plate is imagewise exposed with a violet or ultraviolet laser at a dosage of less than 300 ?J/cm2, and then developed with an aqueous alkaline developer. Higher monomer to polymer weight ratio is advantageously used. A pigment is preferably incorporated into the photosensitive coating solution as a liquid dispersion. The exposed plate is preferably developed on a processor with an alkaline developer coupled with a replenisher having higher pH.

Abstract: A lithographic printing press having a plate cylinder in a light-tight compartment suitable for on-press imaging and developing a violet or ultraviolet laser sensitive plate is described. The plate cylinder as well as certain other press parts is covered by non-transparent or safe-light-only covers so that no or substantially no light or unsafe light passes onto the plate mounted on the plate cylinder during on-press imaging and development. The plate comprises on a substrate a photosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to a violet or ultraviolet laser. The plate is on-press exposed with the laser, developed with ink and/or fountain solution, and then directly prints images to the receiving sheets.

Abstract: High speed violet or ultraviolet laser sensitive lithographic printing plate comprising on a substrate a specific photosensitive composition is described. The photosensitive layer comprises a multifunctional (meth)acrylate monomer, a hexaarylbiimidazole compound, and a sensitizing dye. Combination of both multifunctional urethane (meth)acrylate monomer and multifunctional non-urethane (meth)acrylate monomer can be advantageously used. The plate is imagewise exposed with a violet or ultraviolet laser at a dosage of less than 1000 ?J/cm2, and then developed either off press or on press.

Abstract: New photoresists are provided that are suitable for short wavelength imaging, including sub-300 nm and sub-200 nm such as 193 nm and 157 nm. Photoresists of the invention contain a resin with photoacid-labile groups, one or more photoacid generator compounds, and an adhesion-promoting additive compound. Photoresists of the invention can exhibit significant adhesion to SiON and other inorganic surface layers.

Abstract: A method of developing a laser sensitive lithographic printing plate with ink and/or fountain solution is described. The printing member comprises on a substrate a photosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to a laser. The plate is exposed with a laser and deactivated under a safe light or in the dark, and then on-press developed with ink and/or fountain solution preferably under white light. Alternatively, the plate is developed with ink and/or fountain solution or the likes off press, and then mounted on press for lithographic printing.

Abstract: Method of on-press developing a thermosensitive lithographic printing member with ink and/or fountain solution is described. The printing member comprises on a substrate a thermosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to an infrared radiation. The printing member can be a pre-coated plate or can be prepared on press by coating a thermosensitive layer onto a substrate that is a sheet material or a seamless sleeve mounted on a plate cylinder or is the surface of a plate cylinder of the lithographic press.

Abstract: Negative thermosensitive lithographic printing plates comprise on a hydrophilic substrate an oleophilic thermosensitive layer comprising a polymeric binder, urethane (meth)acrylate monomer having at least 6 (meth)acrylate groups, a non-urethane (meth)acrylate monomer having at least 4 (meth)acrylate groups, a free-radical initiator, and an infrared absorbing dye; wherein the weight ratio of said urethane (meth)acrylate monomer to said non-urethane (meth)acrylate monomer is from 0.10 to 3.0, and said thermosensitive layer is capable of hardening upon exposure to an infrared radiation. Lithographic plates with such compositions have excellent press durability.

Abstract: Negative thermosensitive lithographic printing plates developable with a non-alkaline aqueous developer and method of developing such plates. The plate comprises on a substrate a thermosensitive layer comprising an ethylenically unsaturated monomer, a free radical initiator, and an infrared absorbing dye. The plate can be imagewise exposed with an infrared laser to cause hardening in the exposed areas and then developed with a non-alkaline aqueous developer to remove the non-exposed areas. The non-alkaline aqueous developer can be water or an aqueous solution comprising at least 60% of water and having a pH of 2.0 to 10.0.

Abstract: New methods and compositions are provided that enable application and processing of photoresist as thick coating layers, e.g. at dried layer (post soft-bake) thicknesses of in excess of 2 microns. Resists can be imaged at short wavelengths in accordance with the invention, including 248 nm.

Abstract: New photoresist compositions are provided that contain a halogenated salt, particularly a halogenated counter ion of an ammonium or alkyl ammonium salt. Preferred photoresists of the invention are chemically-amplified positive resists and contain an ammonium or alkyl ammonium salt that has a halogenated anion component such as a halogenated alkyl sulfonate or carboxylate anion component. Inclusion of the halogenated organic salt in a photoresist composition can provide enhanced lithographic performance.

Abstract: A variable data lithographic printing device comprises surrounding a printing cylinder a photosensitive layer coater, an exposure source, optionally a developer, an inking applicator, optionally a transfer system, and optionally an eraser. During printing operation, each surface areas of the rotating cylinder continuously undergo the cycle of coating, imagewise exposure, optionally developing, inking, printing of inked images to the receiving medium, and optionally erasing processes. The developing means can be omitted if an ink and/or fountain solution developable photosensitive layer is used. In an alternative design, the cylinder is replaced with a continuous supply of a ribbon with lithographic substrate surface. In another alternative design, the cylinder and the coater are replaced with a continuous supply of a pre-sensitized ribbon comprising on a substrate a photosensitive layer.

Abstract: Lithographic printing plates having on a hydrophilic substrate an oleophilic photosensitive layer comprising an oleophilic polymer, a free radical polymerizable monomer, and 4-piperonyl-2,6-bis(trichloromethyl)-s-triazine as free radical initiator and/or leucomalachite green as exposure indicating dye; wherein the weight ratio of the monomer to the polymer is larger than 1.0. The plates can be developed with ink and/or fountain solution on a lithographic printing press or with a non-alkaline aqueous developer comprising 60-99% by weight of water and 0.5 to 40% by weight of an alcohol solvent. A photosensitive dye can be added in the photosensitive layer to provide photosensitivity to a specific wavelength between 200 and 1200 nm. Unlike commonly used s-triazine initiator or leuco dye, 4-piperonyl-2,6-bis(trichloromethyl)-s-triazine or leucomalachite green does not insolubilize from the photosensitive layer.

Abstract: Negative thermosensitive lithographic printing plates developable with a non-alkaline aqueous developer and method of developing such plates. The plate comprises on a substrate a thermosensitive layer comprising an ethylenically unsaturated monomer, a free radical initiator, and an infrared absorbing dye. The plate can be imagewise exposed with an infrared laser to cause hardening in the exposed areas and then developed with a non-alkaline aqueous developer to remove the non-exposed areas. The non-alkaline aqueous developer can be water or an aqueous solution comprising at least 60% of water and having a pH of 2.0 to 10.0.

Abstract: New photoresists are provided that are suitable for short wavelength imaging, including sub-300 nm and sub-200 nm such as 193 nm and 157 nm. Resists of the invention comprise a polymer component that contains one or more adhesion-promoting groups that can impart enhanced adhesion of a coating layer of a photoresist containing the polymer to an underlying substrate, including a SiON layer.

Abstract: A variable data lithographic printing device comprises surrounding a printing cylinder a photosensitive layer coater, an exposure source, optionally a developer, an inking applicator, optionally a transfer system, and optionally an eraser. During printing operation, each surface areas of the rotating cylinder continuously undergo the cycle of coating, imagewise exposure, optionally developing, inking, printing of inked images to the receiving medium, and optionally erasing processes. The developing means can be omitted if an ink and/or fountain solution developable photosensitive layer is used. In an alternative design, the cylinder is replaced with a continuous supply of a ribbon with lithographic substrate surface. In another alternative design, the cylinder and the coater are replaced with a continuous supply of a pre-sensitized ribbon comprising on a substrate a photosensitive layer.

Abstract: New photoresists are provided that are suitable for short wavelength imaging, including sub-300 nm and sub-200 nm such as 193 nm and 157 nm. Photoresists of the invention contain a resin with photoacid-labile groups, one or more photoacid generator compounds, and an adhesion-promoting additive compound. Photoresists of the invention can exhibit significant adhesion to SiON and other inorganic surface layers.

Abstract: The present invention relates to new polymers that contain repeat units of phenol and photoacid-labile esters that contain an alicyclic group, preferably a bulky group that suitably may contain 7 to about 20 carbons, such as an alkyladamantyl, ethylfencyl, tricyclo decanyl, or pinanyl group. Polymers of the invention are useful as a component of chemically-amplified positive-acting resists.

Abstract: New photoresist compositions are provided that contain a halogenated salt, particularly a halogenated counter ion of an ammonium or alkyl ammonium salt. Preferred photoresists of the invention are chemically-amplified positive resists and contain an ammonium or alkyl ammonium salt that has a halogenated anion component such as a halogenated alkyl sulfonate or carboxylate anion component Inclusion of the halogenated organic salt in a photoresist composition can provide enhanced lithographic performance.

Abstract: Lithographic printing plates having on a hydrophilic substrate an oleophilic photosensitive layer comprising an oleophilic polymer, a free radical polymerizable monomer, and 4-piperonyl-2,6-bis(trichloromethyl)-s-triazine as free radical initiator and/or leucomalachite green as exposure indicating dye; wherein the weight ratio of the monomer to the polymer is larger than 1.0. The plates can be developed with ink and/or fountain solution on a lithographic printing press or with a non-alkaline aqueous developer comprising 60-99% by weight of water and 0.5 to 40% by weight of an alcohol solvent. A photosensitive dye can be added in the photosensitive layer to provide photosensitivity to a specific wavelength between 200 and 1200 nm. Unlike commonly used s-triazine initiator or leuco dye, 4-piperonyl-2,6-bis(trichloromethyl)-s-triazine or leucomalachite green does not insolubilize from the photosensitive layer.