摘要:
The presence of unwanted ink-receptive sections on developed positive-working lithographic plates due to shading by plate-holding clamps during imaging, is avoided by the use of clamps that are substantially transparent to the imaging radiation. In the case where the plate precursors can be imaged by heat, the presence of unwanted unexposed sections can also be avoided by selectively heating those sections shaded by the clamps, while avoiding heating the image section of the plate.
摘要:
A method for eliminating unwanted ink-receptive sections in positive working printing plates resulting from shading of the surface layer during exposure by the clamps holding the plate on the exposure apparatus following development of an imagewise exposed precursor. Accordingly the areas that are shaded are identified prior to development and the surface layer is scored in those areas to a depth and density sufficient to result in the scored layer being removed during development but not deep enough to damage the underlying hydrophilic layer.
摘要:
A method for forming an image by imaging and developing a multi-layer imageable element, in which the developer is fresh developer and the developer is not reused, is disclosed. Much smaller variation in dot percentage is obtained when each imaged imageable element is developed in fresh developer than when the developer is reused to develop additional imaged imageable elements. The method is especially suited to the formation of images using stochastic screening. Either a solvent based developer or a high pH developer may be used.
摘要:
Apparatus and method for exposing a lithographic printing plate wherein the apparatus includes a plurality of laser diodes emitting light of wavelength between 350 nm and 450 nm. The light from each of the laser diodes is directed onto the lithographic printing plate such that each spot on the lithographic printing plate receives light emitted from at least one of the laser diodes. Preferably, the lithographic printing plate is a violet-sensitive lithographic member and the lithographic member is a printing press plate. The power of each laser diode may be between 5 mW and 30 mW, and preferably the laser diodes emit light of wavelength between 390 nm and 430 nm.
摘要:
A recording medium comprises an oleophilic substrate and, thereover, a topmost oleophobic layer comprising a cured polymeric silicone matrix that consists essentially of the addition-cure reaction product of a vinyl-functional polydialkylsiloxane and a silane cross-linking agent. The vinyl-functional polydialkylsiloxane has a molecular weight ranging from 30,000 to 75,000 or 110,000 to 130,000. If the molecular weight of the vinyl-functional polydialkylsiloxane is within the range of 30,000 to 75,000, the molar ratio of silane groups to vinyl groups is within the range of about 11:1 to about 25:1; and if the molecular weight of the vinyl-functional polydialkylsiloxane is within the range of 110,000 to 130,000, the molar ratio of silane groups to vinyl groups is from about 5:1 to about 27:1. The recording medium may be used as a lithographic printing plate.
摘要:
Ablation-type printing plates having increased shelf-life are produced using a melamine resin free of water prior to use. A representative production sequence includes providing a substrate having an oleophilic surface; coating, over the substrate, an oleophilic resin composition having (A) a resin phase consisting essentially of a melamine resin substantially free of water and a resole resin, the resole resin being present in an amount ranging from 0% to 28% by weight of dry film, (B) a near-IR absorber dispersed within the resin phase, and (C) a sulfonic acid catalyst dispersed within the resin phase and being present in an amount ranging from 0.7% to 1.6% by weight of dry film; curing the resin composition to produce a dry film; following resin curing, coating an oleophobic polymer composition over the cured resin composition; and curing the oleophobic polymer composition.
摘要:
In ablation-type printing plates involving silicone acrylate top layers, curing at high oxygen levels not only substantially reduces or eliminates toning, but does not adversely affect plate durability or printing performance.
摘要:
Gum solutions are formulated to protect a negative-working photopolymer imaging layer coated on an anodized aluminum substrate that has undergone a post-anodic sealing treatment with inorganic phosphate and inorganic fluoride, followed by development. In various embodiments, the developer and gum solution have different compositions but contain at least one polycarboxylic acid—which may be a polymer—that beneficially desensitizes the surface after the unexposed photopolymer layer is removed.
摘要:
Negative-working imagable elements can be imaged and then developed using a lower pH organic-based single-phase developer that is less toxic and corrosive and that can be more readily disposed of after use. This developer has a pH less than 12 and comprises a) an amphoteric surfactant comprising a nitrogen-containing heterocycle, b) an amphoteric surfactant having two or more nitrogen atoms, or c) an amphoteric surfactant of a) and an amphoteric surfactant of b).
摘要:
A game cartridge is described that retains a player's current holdings related to game play in a write-once memory. The cartridge thus becomes closely identified with the previous play of a player to simulate non-electronic collectable card or other status games. Further, some aspects of the invention allow for initialization of the player's holdings. In one embodiment of the present invention, the game cartridge provides an environment for playing a collectable card game, such as a POKÉMON™-type game, and the game cartridge remembers and can update the current holdings of electronic cards. The game cartridges of the present invention are collectable items in that they retain a current accounting of a player's holdings and can be traded among different players.