摘要:
A method for forming a printing plate from a printing plate precursor having a radiation-sensitive layer, sensitive to radiation in a first frequency spectrum such as the far or near infrared, and to radiation in a second frequency spectrum other than the first frequency spectrum such as visible or ultraviolet. The plate is exposed twice. Once to imaging radiation in the first frequency spectrum and again to radiation in the second frequency spectrum. The second frequency spectrum exposure is done only to the areas of the plate undesirably shaded during the imagewise exposure.
摘要:
A negative-working imageable element has an imageable layer that includes an initiator composition including an iodonium cation and a boron-containing anion at a molar ratio of at least 1.2:1, an infrared radiation absorbing compound, a primary polymeric binder, and a spirolactone or spirolactam colorant precursor. The imaged element exhibits improved print-out.
摘要:
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.
摘要:
A positive-working imageable element comprises inner and outer layers and a radiation absorbing compound such as an IR absorbing dye. The inner layer includes a polymeric material that is removable using an alkaline developer. An ink receptive outer layer is not removable using an alkaline developer before its exposure to imaging radiation. The outer layer includes a polymer binder having pendant epoxy groups that are substantially unreacted during exposure.
摘要:
A negative-working imageable element has an imageable layer and a topcoat layer that contains a composition that will change color upon exposure to imaging infrared radiation. The imageable element can be imaged and developed on-press to provide images with improved contrast for print-out.
摘要:
The present invention relates to negative-working imageable elements that can be used for the manufacture of printing plates. These imageable elements can be developed on on-press by the action of a lithographic printing ink used in combination with either water or a fountain solution. The imageable elements comprise an imageable layer that is not removable in water or fountain solution alone. The imageable layer includes a free radically polymerizable compound, a free radical initiator composition, an infrared radiation absorbing compound, and a polymeric binder comprising poly(alkylene oxide) pendant groups, and preferably additionally pendant cyano groups.
摘要:
The present invention provides methods of imagewise exposing a thermally sensitive composition formed from a nanopaste comprising inorganic nanoparticles, a carrier, and preferably certain polymeric binders. The composition has been applied to a substrate and treated to improve adhesion. Exposure affects the solubility of exposed portions of the applied and treated layer relative to unexposed portions of the applied layer. The imaged layer is then developed on-press with a fountain solution, lithographic ink, or both, to remove the exposed portions or unexposed portions of the layer to form an image in a printing plate.
摘要:
The present invention relates to negative-working imageable elements that can be used for the manufacture of printing plates. These imageable elements can be developed on on-press by the action of a lithographic printing ink used in combination with either water or a fountain solution. The imageable elements comprise an imageable layer that is not removable in water or fountain solution alone. The imageable layer includes a free radically polymerizable compound, a free radical initiator composition, an infrared radiation absorbing compound, and a polymeric binder comprising poly(alkylene oxide) pendant groups, and preferably additionally pendant cyano groups.
摘要:
Infrared absorbing compounds in which the anion is selected from the group consisting of 5-isatinsulfonate, 10-camphorsulfonate, and 4,5-dihydroxy-1,3-benzenedisulfonate are disclosed. Negative-working imageable elements containing these compounds have improved dot stability.
摘要:
Processes for imaging and developing imageable elements useful as lithographic printing plate precursors either thermally or with ultraviolet radiation that use the same developer are disclosed. The imageable elements comprise a top layer and an underlayer. The top layer contains a phenolic polymer and a material that has either the o-benzoquinonediazide functionality or the o-diazonaphthoquinone functionality. The developer is a 20:80 to 80:20 mixture of (1) an aqueous alkaline developer that has a pH greater than 11 and contains about 2 wt % to about 8 wt % of an alkali metal silicate, and (2) a solvent based developer that contains about 0.5 wt % to about 15 wt % of an organic solvent or mixture of organic solvents.