摘要:
There is described a method of preparing a water-less lithographic printing form using a precursor which includes a support having a coating thereon comprising a diazo salt formed from an aromatic diazonium compound and an abhesive counter anionic moiety, the method comprising heat mode imaging the precursor and processing the imaged percursor on press by the application of printing ink to remove the abhesive products of the imaging so that areas of the precursor which have been imaged are ink-accepting.
摘要:
A lithographic imaging member, such as a printing plate, has a support having thereon an ink-accepting melanophilic layer and an ink-rejecting siloxane surface melanophobic layer. Within the printing plate is a photothermal conversion material capable of converting irradiation, such as IR radiation, to heat in exposed regions. Also within one of the layers is a compound that upon imaging releases a moiety that facilitates degradation of the surface melanophobic layer. The released moiety can be fluoride ion or a fluoride ion-containing compound. In some imaging members, a barrier layer may be interposed between the two other layers. Such imaging members can be digitally imaged and used for printing without post-imaging processing.
摘要:
A formulation comprising a heat sensitive cross-linkable ink and carbon black is coated over substantially the entirety of an ink-repellent/ink-releasing surface of a printing cylinder of a printing press by heating the formulation and/or the outer surface of the printing cylinder so that the formulation adheres to the cylinder to provide a continuous coating thereon. The coated printing cylinder is then allowed to cool to ambient temperature whereafter it can be imaged using a digitally controlled laser. The imaged printing cylinder may be developed during press start up by application of waterless ink over the cylindter surface in order to remove the non-imaged areas comprising non-cross-linked ink. After completion of printing, the printing cylinder can be cleaned by using an appropriate solvent to solubilize the cross-linked ink in the imaged areas and subsequently re-used.
摘要:
This invention discloses lithographic printing plates having a thin releasable interlayer interposed between a rough and/or porous substrate and a radiation-sensitive layer. The radiation-sensitive layer is bonded to the rough and/or porous substrate through mechanical interlocking. Insertion of a thin releasable interlayer in such a configuration minimizes cross-contamination between the substrate and the radiation-sensitive layer, protects the substrate from attack by environmental species and reduces ink scumming tendency of the plates while still allowing good bonding between the substrate and the radiation-sensitive layer.
摘要:
A substrate is coated with a first material which is soluble in a first solvent, whereupon a second material which is strongly adherent to the first material and insoluble in the first solvent is selectively applied by an ink jet printer. The substrate is then developed in the first solvent to establish the image. In a preferred embodiment the substrate is hydrophilic, the first material is a negative working photosensitive material, and the second material is a transparent adhesive, which permits curing the first material by exposure to actinic light after the development step. The adhesive is then removed. In an embodiment directed to a waterless plate the substrate includes a surface coating of silicone, and the first material is a primer which promotes adhesion of a second material in the form of an oleophilic adhesive which is selectively applied. The primer is then developed to expose the silicone on the non-image areas. The ink carrying image areas are formed by the adhesive, which in this embodiment is not removed.
摘要:
Lithographic plate compositions and a method for their production have been discovered that are especially useful in conjunction with digitally controlled lasers to directly construct printable images on lithographic plates. The plates comprise a substrate and an ablatable polymeric coating on the substrate where the ablatable, imageable coating is prepared by in situ or solution polymerization of conjugated monomers deposited on the plate by vapor deposition or in solution. Examples of such monomers are thiophene, pyrrole and aniline.
摘要:
A lithographic printing plate precursor requiring no fountain solution possible to conduct heat mode recording by a laser beam and excellent in image reproducibility and scratch resistance, which comprises a support having provided thereon a light-heat conversion layer containing a compound converting a laser beam to heat and a silicone rubber layer in this order, wherein the light-heat conversion layer contains an addition polymer having a group capable of reacting with a silicone crosslinking agent at a side chain thereof, and the addition polymer reacts with a silicone crosslinking agent contained in the silicone rubber layer when the silicone rubber layer is formed by coating and drying.
摘要:
The present invention provides a method for making a lithographic printing plate requiring no dampening liquid comprising the steps of:image-wise exposing using a laser beam a heat mode recording material comprising on a support having an oleophilic surface (i) a recording layer having a thickness of not more than 3 .mu.m and containing a substance capable of converting the laser beam radiation into heat and (ii) a cured oleophobic surface layer and wherein said recording layer and oleophobic surface layer may be the same layer;rubbing the exposed heat mode recording material thereby removing said oleophobic surface layer in the exposed areas so that the underlying oleophilic surface is exposed andavoiding the swelling of said oleophobic surface layer by carrying out said rubbing without the use of a liquid or with the use of a non-solvent for said oleophobic surface layer.
摘要:
A process for preparing a waterless lithographic printing master is provided. A suitable substrate, which is preferably ink accepting is first coated with a curable silicone which is curable at low or elevated temperature and a second different curable silicone deposited on said first silicone which can be preferentially cured at a lower temperature without curing the first silicone and which second silicone contains, in addition to its own catalyst, an amount of high temperature curing catalyst sufficient to cure the underlying silicone. The surface silicone is then preferentially cured at least on its surface to render it nontacky, but not the underlying silicone. A particulate image pattern is deposited on the surface cured silicone which pattern comprises a material which selectively inactivates the curing catalyst and combines with the catalyst to degrade the cured silicone below said image pattern at elevated temperature, the underlying silicone cured in the nonimaged areas to an elastomeric ink releasable condition, as well as the surface layer to the extent that it was not previously rendered ink releasing, and the particulate image pattern and preferably the degraded and uncured silicones removed beneath said pattern to reveal the ink accepting substrate in image configuration.
摘要:
A novel method of preparing a waterless lithographic master and a method of printing therefrom are provided. To prepare the printing master, a suitable ink accepting substrate such as aluminum, paper or plastic, is coated with a silicone gum curing catalyst, preferably suspended in a hydrophilic binder. A barrier fusable particulate hydrophobic image pattern is then deposited on said coated substrate and fused to mask said curing catalyst in the image areas. The substrate is then coated with an uncured silicone gum, preferably as an aqueous emulsion so that the gum does not adhere to the hydrophobic image pattern. The silicone gum is then cured in the nonimage areas to selectively provide ink receptive image areas and ink releasing nonimage areas. The method of printing comprises the additional steps of applying ink to the imaged master and contacting the inked master with an image receiving surface to thereby transfer the inked image.