Abstract: The invention relates to coating solutions, processes for the preparation of a printing plate using these coating solutions as well as printing plates prepared in this manner; in particular, the invention relates to printing plates the photosensitive layer of which contains homogeneously distributed polymer particles.

Abstract: A method of preparing a planographic printing member is disclosed. In one embodiment, the method comprises forming a hydrophilic layer by thermally spraying a hydrophilic particulate material onto an ablatable layer. Typical hydrophilic materials are SiO2, Al2O3, Cr2O3, TiO2 and ZrO2. Spraying a plasma containing the hydrophilic material in an inert gas atmosphere is preferred method for forming the hydrophilic layer.

Abstract: An imaging device comprising an electro-optic modulator for modulating incident laser beams; an array of adjacent electrodes comprising a group of imaging electrodes addressed in accordance with image information; means to illuminate an area slightly larger than the width of said imaging electrodes; and one or more additional electrodes located on each side of said group of imaging electrodes to permanently direct extraneous marginal beams to light-stop means so that only the light emerging from the imaging electrodes is allowed to reach a light sensitive medium.

Abstract: A lithographic printing plate precursor element is made by coating a support web, with a thermal insulating layer, and then overcoating with a coextensive ink repellent layer. The coextensive ink repellant layer comprises a crosslinked polymeric matrix containing a colloid of an oxide or a hydroxide of a metal selected from the group consisting of beryllium, magnesium, aluminum, silicon, gadolinium, germanium, arsenic, indium, tin, antimony, tellurium, lead, bismuth, a transition metal and combinations thereof. A photothermal conversion material is present in the ink repellent layer, in a stratum located between the thermal insulating layer and the ink repellent layer, or in both the ink repellent layer and the stratum. The ink repellant layer contains less than 5% hydrocarbon groups by weight.

Abstract: A laser sensor holder apparatus for enabling a power sensor to be held in the path of a laser beam to measure the beams power comprises a base unit including a mounting frame, and translation stages to enable the movement of a sensor mounting plate to a desired position in the path of a laser beam. The apparatus is useful in measuring the power of a laser beam. Applications of the apparatus include its use in direct imaging systems whereby the previous method of manually holding a power sensor in the path of a class 4 laser and all of its inherent disadvantages may be avoided.

Abstract: An imaging member, such as a negative-working printing plate, can be prepared using a hydrophilic heat-sensitive imaging layer comprised of a hydrophilic heat-sensitive, crosslinked vinyl polymer containing recurring organoonium groups. The imaging member can also include a photothermal conversion material such as carbon black or an infrared radiation absorbing dye. The heat-sensitive polymer has recurring units containing an organoammonium, organophosphonium or organosulfonium group that reacts to provide increased oleophilicity (ink receptivity) in response to heat. Heat is preferably generated by laser irradiation in the IR region of the electromagnetic spectrum. The heat-sensitive polymer is considered “switchable” in response to heat. The imaging member can be used in printing methods without the usual wet processing steps.

Abstract: An imaging member, such as a negative-working printing plate, can be prepared using a hydrophilic imaging layer comprised of a heat-sensitive hydrophilic polymer having a positively charged moiety, and optionally a photothermal conversion material. The heat-sensitive polymer has recurring units containing an N-alkylated aromatic heterocyclic group or an organoonium group that reacts to provide increased oleophilicity in areas exposed to energy that provides or generates heat. For example, heat can be supplied by laser irradiation in the IR region of the electromagnetic spectrum. Thus, the heat-sensitive polymer is considered “switchable” in response to heat, and provides an imaging means without wet processing.

Abstract: There is described a method of preparing a positive working water-less lithographic plate which comprises a support having an oleophilic surface, there being coated on the support a mixture which comprises as one component an ink-repellant and water-repellant polymer or a mixture of such polymers or polymer precursors, and as the other essential component of the mixture an infra-red or heat sensitive composition selected from (a) an organic solvent soluble diazo compound and an infra-red absorbing compound, (b) a photopolymer and an infra-red absorbing dye, or (c) a mixture of a free-radically polymerisable ethylenically unsaturated compound or compounds together with either a photoinitiator which is infra-red sensitive or an initiator which is heat sensitive together with an infra-red absorbing compound, the ratio of ink-repellant polymer to infra-red or heat sensitive composition (a), (b) or (c) in the mixture being from 20-80 ink repellant polymer to 80-20 infra-red or heat sensitive composition by weight,

Abstract: A radiation sensitive plate structure and method for digitally producing a lithographic printing plate. The radiation sensitive plate structure comprises a substrate, a photosensitive layer which changes solubility in a developer liquid upon exposure to actinic radiation, and a photographic layer. The photographic layer comprises a silver halide emulsion dispersed in gelatin, a sensitizing dye, and an adhesion promoting component comprising a vinyl phenol copolymer and a polymeric keying agent. The method for digitally producing a lithographic printing plate comprises the following steps. The radiation sensitive plate structure is provided and the photographic layer is image-wise exposed to visible or laser radiation to form an exposed photographic layer. The exposed photographic layer is developed to form an opaque image mask.

Abstract: A presensitized printing plate intermediate having an image mask on a UV radiation transparent removable coating layer; and a printing plate produced directly by reactants which polymerize alone or in combination with other reactants precoated on the plate substrate to form a printable hard resin image. A method of digitally forming an image on said printing plate intermediate.

Abstract: An imaging member is prepared by applying to a support a heat-sensitive imaging layer which comprises at least one heat-sensitive polymer capable of undergoing transformation from a hydrophilic to hydrophobic state or hydrophobic to hydrophilic state, wherein the transformation occurs such that the activation energy Ea and the Arrhenius pre-exponential factor A associated with the transformation simultaneously fulfill the relationships: ln (A).gtoreq.0.4 Ea+8.84 and ln (A).ltoreq.1.69 Ea-14.37. The imaging member is useful in processless thermal lithographic printing.

Abstract: An aqueous alkaline composition comprising at least one phosphonic acid, at least one polyglycol derivative and at least one glycol. The composition can be used as either a developer or a replenisher for either positive-working or negative-working alkaline developable lithographic printing plates, including thermal plates.

Abstract: A planographic printing plate includes a radiation sensitive layer which may comprise a rubber material. Application of heat causes exposed areas to be vulcanized. The plate may be developed by applying a force to the radiation sensitive layer, for example by rubbing, thereby to remove non-exposed areas.

Abstract: A precursor element for making a lithographic printing plate is composed of a support, an ink receptive thermal conversion inner layer and a sol-gel, ink repellent outer layer. The outer sol-gel layer containes crosslinked colloids derived from certain metal oxides or hydroxides. The plates produced from the ellements are long-running plates that require no post-imaging processing.

Abstract: The present invention is directed to a system and a method for illuminating imaging radiant energy from a laser source onto a spatial modulator. It comprises means or a step of focusing the radiant energy from the laser source at a focal point. There is further provided a mixing means mixing the radiant energy substantially at or downstream the focal point, the mixing means having an input, a plurality of reflecting surfaces and an output, wherein the reflecting surfaces are arranged so that upon entry of the radiant energy into the input of the mixing means the radiant energy is subjected to multiple reflections and at the output the distribution of the radiant energy is substantially uniform.

Abstract: A method for preparing a waterless lithographic plate is disclosed. A mixture that contains a water-repellant release material and a compound that becomes aqueous developable on heating is coated on a support, heated imagewise, and developed to produce the printing plate. Preferred water-repellant release materials are acrylic and methacrylic polymers with fluorinated side chains and silicone containing polymers, especially organo functional siloxanes. Preferred compounds that become aqueous developable on heating are phenolic resins as well as complexes of phenolic resins with quinolinium compounds, benzothiazolium compounds, pyridinium compounds, and imidazoline compounds.

Abstract: An infrared imaging composition contains two essential components, a non-basic infrared radiation absorbing material (such as carbon black), and a phenolic resin that is either mixed or reacted with an o-diazonaphthoquinone derivative. These compositions are useful in positive-working or negative-working imaging elements such as lithographic printing plates that can be adapted to direct-to-plate imaging procedures.

Abstract: A method for making a lithographic printing plate comprising exposing a support, a melonophilic layer and a melonophobic layer, the latter containing crosslinked colloids to a laser beam having an intensity greater than 0.1 mW/.mu..sup.2 for a time sufficient to give a total exposure of about 200 milliJoules/cm.sup.2 or greater. Good printing steps and long running plates are produced.

Abstract: A method for preparing a substrate for a planographic printing plate is disclosed. A liquid that contains water; a soluble alkali metal silicate, preferably sodium silicate; and a dispersed particulate material is coated on a substrate, preferably aluminum or an aluminum alloy, to produce a hydrophilic layer on the substrate. A layer of image material may be coated over the substrate to produce a planographic printing plate. In one embodiment the liquid contains a mixture of two particulate materials: alumina and titanium dioxide.

Abstract: Coated paper stocks for electrostatic imaging comprising a substrate coated on at least one surface with a resin layer comprised of olefinic material and a pin-hole free, continuous coating layer over said resin layer. The continuous layer has a glass transition temperature above 100.degree. C. and is comprised of one or more natural or synthetic film forming polymers. As a single layer this continuous coating layer functions as both a heat protective and imaging layer. In an alternate embodiment two separate coating layers are provided with separate heat protective and imaging functionalities.