Abstract: Polymeric acetal resins useful in lithographic printing are disclosed. The polymeric acetal resin contains units (A), (B), (C), (D), and (E). Unit (A) is a vinyl alcohol unit. Unit; (B) is a polyvinyl acetal unit containing an R group, where R is hydrogen, an aliphatic group, an aromatic group, or an arylaliphatic group. Unit (C) is a vinyl carboxylate unit. Unit (D) is an acidic vinyl acetal unit and/or a residue of an acidic vinyl monomer. Unit (E) is a free radical polymerization-inhibiting vinyl acetal unit and/or a free radical polymerization-inhibiting vinyl alcohol ester unit. The resin comprises about 10 to about 60 mol % of unit (A), about 5 to about 60 mol % of unit (B), about 0.3 to about 30 mol % of unit (C), about 1 to about 40 mol % of unit (D), and about 0.01 to about 2 mol % of unit (E).

Abstract: The invention provides a lithographic printing for precursor having an imagable coating on an aluminum support, wherein the imagable coating comprises a polymeric substance comprising colorant groups, and wherein the aluminum support on which the coating is provided is anodized but not subsequently modified by means of a post-anodic treatment compound, and the coating does not comprise a colorant dye. The polymeric substance may also comprise pendent infra-red or developer dissolution inhibiting groups, and these groups may also be the colorant groups themselves.

Abstract: The invention is directed to various calibration techniques for calibrating an imagining device such as a display device, a printer, or a scanner. The techniques may involve characterizing the imaging device with a device model such that an average error between expected outputs determined from the device model and measured outputs of the imaging device is on the order of an expected error, and adjusting image rendering on the imaging device to achieve a target behavior. The invention can achieve a balance between analytical behavior of the imaging device and measured output. In this manner, adjustments to image rendering may be more likely to improve color accuracy and less likely to overcompensate for errors that are expected.

Abstract: A thermally imagable article comprises a substrate on which is coated a positive working heat-sensitive composition comprising a hydroxyl group-containing polymer and a heat-labile moiety which decreases the developer solubility of the composition as compared to the developer solubility of the composition without the heat-labile moiety, wherein the heat-sensitive composition does not comprise an acid generating moiety. The invention also provides novel positive working compositions comprising heat-labile moieties, and imagable articles comprising said compositions.

Abstract: A planographic printing member precursor comprises a first component, for example a hydroxy group containing polymer, and a second component which may be a siloxane or a compound of general formula (I), wherein M represents a silicon or a titanium atom and each of R1, R2, R3 and R4 is independently selected from hydrogen or halogen atoms; a hydroxy group; an optionally substituted alkyl, alkenyl or alkynyl group; an optionally substituted alkoxy group; or an optionally substituted saturated or unsaturated cyclic or heterocyclic group. On exposure, the second component reacts with the first component to define an oleophobic/hydrophilic material in exposed areas and in non-exposed areas the second component is removed, on processing of the precursor.

Abstract: A lithographic printing plate processor having an immersion developing tank followed by a developer exit tank in which a printing plate driven through the immersion tank is subjected to a spray of clean developer wherein the exit tank is isolated from the developing tank and there is associated with the exit tank developer spray system a clean developer recirculating loop. The recirculating loop includes a holding tank, a pump and a filter and its elements are isolated, separate and distinct from the developing tank.

Abstract: The present invention relates to printing plate coating compositions comprising: (a) a carbon pigment dispersible in water; (b) at least one polymer comprising at least one ionomeric polymer subunit; and (c) at least one high molecular weight thickening agent which shows pseudoplastic behavior. The printing plate precursor of this invention is prepared by coating a printing plate substrate with the coating composition.

Abstract: An optical head having a laser source of beams at an input end and image forming beams at an output end and a plurality of optical components arranged along the beams between the input and output ends to obtain an image on a photosensitive printing plate from the beams. The optical components include reflecting surfaces adapted to fold the beams several times between the input and output ends times in such a way as to reduce the width and height of the optical head. The folded beams are located in a plurality of parallel surfaces perpendicular to the image formed on the photosensitive printing plate. The optical head further includes optical components adapted to adjust the width, location, orientation and intensity of the image from the beams.

Abstract: A method for the refreshment and reuse of loaded developers used in lithographic printing is disclosed. A polyoxyalkylene derivative is added to a silicate-containing loaded developer. Insoluble material is separated and the alkalinity level of the resulting essentially colorless liquid adjusted to produce a refreshed developer. The refreshed developer may be used to develop additional exposed imageable elements.

Abstract: A direct-to-press imaging method comprises:

Abstract: A lithographic printing plate substrate is conditioned for imaging in a printer engine by attaching a leader to the leading edge. The leader is sufficiently flexible to be drawn into the printer engine and is adapted to pull the plate substrate through the printer engine.

Abstract: The present invention provides a flexible and convenient method that combines a digital color image with the versatility of an analog imaging method to create a hybrid digital/analog image, wherein an analog image is formed directly on a digitally generated image.

Abstract: 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.

Abstract: Thermally imageable elements and methods for their preparation and use are disclosed. The elements contain, in order, a substrate; an underlayer; and an ink-repellent layer. The underlayer contains a crosslinked allyl functional polyurethane. A photothermal conversion material is present in either in the underlayer or in an absorber layer between the underlayer and the ink-repellent layer. Thermal imaging and development removes the ink-repellent layer and reveals the underlayer in the exposed regions to form an imaged element useful as a waterless lithographic printing plate.

Abstract: Positive-working thermally imageable elements, useful as printing plate precursors and having reduced ablation when thermally imaged, and methods for their preparation are disclosed. In one aspect, the elements contain a hydrophilic substrate, an underlayer, a barrier layer, and a top layer. The underlayer comprises a photothermal conversion material.

Abstract: Negative-working, water-developable imageable elements, useful as printing plate precursors, and methods for their use, are disclosed. The elements can be imaged with ultraviolet radiation, with infrared radiation, or with heat. The elements contain an imageable composition that contains a latent Brönsted acid, a water-soluble or water-dispersible binder, and an acid-activated cross-linking agent.

Abstract: The present invention relates to a negative-working radiation imageable lithographic printing plate precursor, preferably having only two polymeric layers on a support. The first (bottom) layer is composed of oleophilic polymers and a photothermal converter which converts radiation to heat. The second polymeric layer (top) is composed of crosslinked hydrophilic polymers which absorb aqueous fountain solution and repel ink. The oleophilic polymers in the first layer contain functional groups are interlayer chemically bonded to the hydrophilic polymer in the second layer to provide interlayer adhesive bonding between the two layers. The plate is imagewise exposed to radiation, such as with an IR laser, resulting in non-ablative adhesion-weakening between the two layers so that the plate can be developed by fountain solution and/or ink on press whereby the top layer in the exposed area is removed on the press to reveal the ink-receptive image area.

Abstract: The present invention includes an imageable element, which can be: (a) an imageable element comprising an imaging layer which comprises: an aromatic diazonium salt containing compound having an alkoxy substituent and an aromatic diazonium salt containing compound free of an alkoxy substituent; a polyvinyl acetal binder; and a sheet substrate; or (b) an imageable element comprising an imaging layer which comprises: an aromatic diazonium salt containing compound having an alkoxy substituent and an aromatic diazonium salt containing compound free of an alkoxy substituent; and a sheet substrate. The imaging layer includes a total aromatic diazonium salt containing compound content of at least 10 weight percent. The molar ratio of the aromatic diazonium salt containing compound having an alkoxy substituent to the aromatic diazonium salt containing compound that is free of an alkoxy substituent is from about 1.0:1 to 70:1. Upon imagewise exposure and development, an imaged element is obtained.

Abstract: A method for manufacturing a microporous film comprising the steps of:

Abstract: Imageable articles comprising positive working polymeric coatings on substrates are given a heat treatment as part of their manufacture, notably at a moderate temperature for an extended period. This heat treatment improves the development characteristics of the coatings in use. It has been found that by carrying out the heat treatment on articles wrapped in a water-impermeable material or in a humidity-enhanced oven, development characteristics may be further improved, especially adjacent to the edges of articles. The imageable articles include precursors for lithographic printing plates and for printed circuits.