Abstract:
Lithographic printing plates are provided by imagewise exposing negative-working lithographic printing plate precursors having a negative-working radiation-sensitive imageable layer, followed by contacting with a processing solution that has a pH of at least 7 and up to and including 11. This processing solution also includes component (1) that is a nitrogen-containing base having an atmospheric pressure melting point of at least 40° C.; component (2) that is a non-ionic surfactant that independently has an atmospheric pressure melting point, glass transition temperature, or pour point of at least 40° C.; component (3) that is a hydroxy-containing solution promoter; and component (4) that is a hydrophilic surface protective compound. The method is carried out in a manner such that the exposed and processed precursor is not further treated with any liquid (such as gumming or rinsing solution) between processing and mounting onto a printing press.
Abstract:
Negative-working lithographic printing plate precursors have improved bakeability and good shelf life and can be imaged using either UV or infrared radiation. These precursors have a negative-working imageable layer that has a unique polymeric binder comprising a polymeric backbone and further comprising at least (a) and (b) pendant groups distributed in random order along the polymeric backbone. The (a) pendant groups are ethylenically unsaturated polymerizable groups, and the (b) pendant groups are defined by Structures (I), (II), and (III) described in the disclosure.
Abstract:
An instrument includes a hollow body with an internal diameter and an optoelectronic image recording system, which is arranged in an end region of the body and has a lens system on an image entrance side. The lens system has a cylindrical section and an image sensor. An external diameter of the cylindrical section is less than the internal diameter of the body, such that an interspace remains between an inner side of the body and an outer side of the lens system, providing access in the body for components. With a viewing direction of 0° to 90° from the optical axis of the lens system, a deflection prism is arranged on the image entrance side at the lens system, and has a section extending laterally beyond the external diameter of the cylindrical section. An image entrance plane of the image sensor runs approximately parallel to the optical axis.
Abstract:
A lithographic printing plate precursor comprises an imageable layer comprising a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye that is defined by Structure (I) shown in the disclosure, which dyes comprise one or more ethylenically unsaturated polymerizable groups in an organic group that is attached to the methine chain. These infrared radiation absorbing dyes exhibit a reduced tendency to crystallize in the imageable layers in the presence of tetraaryl borate counter anions and therefore provide improved shelf life.
Abstract:
Both positive-working and negative-working imageable element can have a radiation-sensitive imageable layer that has at least one pigment colorant that does not change color when heated, and at least one dye that can change color when heated. The dye is soluble in the solvent or mixture of solvents used to coat the radiation-sensitive imageable layer on a substrate and the pigment colorant is not. This combination of pigment colorant and dye provide excellent image contrast after imaging, development, and postbaking. The pigment colorant and the dye independently have a maximum absorption of from about 480 to about 700 nm.
Abstract:
Imaged lithographic printing plates are processed using a developer that is replenished with only water, but replenishment is at a rate to allow developer volume to slowly decrease from a developer reservoir. This allows for a longer processing cycle especially when the developer is supplied from a container having a defined amount and applied using spray devices where water evaporation from the developer can be significant. Water lost by evaporation is replenished while water carried out by lithographic printing plates is not replenished.
Abstract:
Radiation-sensitive element comprising a substrate and a radiation-sensitive coating comprising (a) at least one component selected from photoinitiators and sensitizer/coinitiator systems which absorbs radiation of a wavelength in the range of 250 to 1,200 nm; (b) at least one free-radical polymerizable oligomer A having an average molecular weight in the range of 3,500 to 9,000 determined by GPC, obtainable by reacting a triisocyanate with (i) at least one acrylic or methacrylic monomer with two free OH groups and at least one (meth)acrylic group and (ii) at least one compound comprising one OH group, at least one (meth)acrylic group and at least one poly(alkyleneoxide) chain in the molecule, wherein the (meth)acrylic monomer (i) is present in an amount of 2 to 20 mole-%, based on the total amount of (meth)acrylic compounds with OH functionality.
Abstract:
Method is described for producing an imaged lithographic printing plate from a precursor comprising a free-radical polymerizable coating and an oxygen-impermeable overcoat, characterized in that removing the overcoat, developing and gumming is carried out in one single step.
Abstract:
The invention relates to processing imaged precursors such as lithographic printing plates. The invention relates specifically to adjusting a processing device for optimal processing performance using a plate recognition system that includes a senseing and authenication subsystem. The processor is automated to make adjustments according to the information provided.
Abstract:
Radiation-sensitive element comprising (a) a substrate and (b) a radiation-sensitive coating comprising (i) at least one component selected from photoinitiators and sensitizer/coinitiator systems which absorbs radiation of a wavelength in the range of 250 to 1,200 nm; (ii) at least one oligomer A of formula (I) wherein X1, X2 and X3 are independently selected from straight-chain or cyclic C4-C12 alkylene and C6-C10 arylene, a heterocyclic group, a heteroaromatic group and combinations of two or more of the above, R1, R2 and R3 are independently selected from (II) and (III) with the proviso that (1) n=0 in at least one of the groups R1, R2 and R3, and (2) n>2 in at least one of the groups R1, R2 and R3, and (3) at least one group R6 is different from H in formula (III).