Abstract: A heat-sensitive composition, for example a coating on a lithographic printing plate, comprises a carboxylic acid derivative of a cellulosic polymer. The composition may contain a radiation absorbing compound and suitable electromagnetic radiation, preferably infra-red radiation, may be used to heat the composition imagewise. The presence of the cellulosic polymer enhances resistance to certain organic liquids.

Abstract: An aqueous developer for imageable elements that contain a radiation-sensitive initiator system and at least one free radical polymerizable material is disclosed. The developer develops these plates quickly, with high throughput, but with no sludge formation in the developing process. The developer contains water, a buffer, and one or more filter dyes and/or one of more free radical inhibitors. The imageable elements are useful as printing plates.

Abstract: The present invention provides a photosensitive lithographic printing plate which displays superior ink receptivity and superior film strength of the photosensitive layer (image area). The photosensitive lithographic printing plate is produced by providing, on top of a support, a photosensitive composition comprising a fluororesin having a fluoro aliphatic group of 3 to 20 carbon atoms in which at least two of three terminal hydrogen atoms are substituted for fluorine atoms, and an ethylene based unsaturated group, as well as a negative photosensitive compound.

Abstract: A photoconductive composition useful for the preparation of printing plates is disclosed. The composition comprising an organic photoconductor, a charge carrier generating material, and a binder comprising a mixture of at least two copolymers. Copolymer (a) comprises an aromatic vinyl monomer, such as styrene or a substituted styrene, and maleic acid anhydride ring opened with a first aliphatic alcohol.

Abstract: A printing plate useful in lithographic printing is prepared by the process comprising: (a) applying an alkali soluble composition comprising at least one polymer composition to a hydrophilic surface on a substrate to provide the surface face with at least one layer which is alkali soluble at a pH in the range of about 6.0 to 14.0; (b) imaging the coated substrate electrostatically with a toner composition; (c) heating the imaged substrate a first time to a temperature greater than the glass transition temperature of the toner composition; (d) contacting the imaged substrate with an aqueous alkaline solution having a pH in the range of about 6.0 to about 14.0; and (e) heating the imaged substrate a second time to a temperature greater than the glass transition temperature of the toner composition. This printing plate is capable of long runs on press with good image quality and advantageously minimizes the occurrence of undesirable background toner “specking” on press.

Abstract: The present invention is a process for fabricating color images using an ink jet printing system. Color formation is achieved using color dye forming chemistry used in silver halide photography. The images formed in this process are light fast, water fast and of a color gamut range similar to photographic media. The image substrate can be either a transparency or opaque media and the final image will be of photorealistic quality.

Abstract: A laser imager comprises a modulator with an array of electrodes to control picture elements individually or by groups to produce images on a recording plane. The light intensity of each picture element or group of elements is determined by electrical potential applied between sets of controlling electrodes. These levels can be manually set or automatically exercised during a balancing routine through a feed-back loop using a photodetector to monitor and detect elements producing a light intensity higher than a set value. Control means assign to these elements a “correction voltage” to lower the density of elements they control. These correction values obtained after one or repeated balancing routines are stored in a memory and are used during the imaging cycle to produce images of substantially equal intensity on the recording medium.

Abstract: A method for preparing a substrate for a planographic printing member is disclosed. A liquid that contains water; a soluble alkali metal silicate, preferably sodium silicate; and a dispersed particulate material is coated on a support, to produce a hydrophilic layer on the support. A layer of image material may be coated over the hydrophilic layer to produce a planographic printing member. In one embodiment the liquid contains a mixture of two particulate materials, preferably alumina and titanium dioxide. The substrate has a surface roughness of about 0.1 &mgr;m to 2 &mgr;m. The substrate is suitable for preparing a planographic printing member processable to a resolution of 10 &mgr;m or less and in which the dots having a roundness of less than 2 are formed.

Abstract: A printing plate is prepared by the process comprising: (a) providing a substrate; and (b) applying by ink jetting to the substrate a fluid composition comprising an acidic polymeric compound and a second compound comprising a pyridyl group in non-aqueous solvent, providing a printing plate that is ready-to-use on a press without having to develop it. The printing plate of this invention is capable of extended press run length and advantageously avoids the costly and time-consuming need of chemical development.

Abstract: A thermally imageable element, useful as a lithographic printing plate precursor is disclosed. The element comprises a hydrophilic substrate; an underlayer comprising a first polymeric material; and an ink-receptive top layer comprising a second polymeric material. Preferably, the top layer comprises a compound that functions as a solubility-suppressing component. The solubility-suppressing component may be a separate dissolution inhibitor compound and/or the second polymeric material may also function as a solubility-suppressing component. On thermal exposure the exposed regions of the top layer becomes more readily soluble in an aqueous developer, allowing the developer to remove the top layer and reveal the surface of the hydrophilic substrate. The lithographic printing plate thus formed has excellent properties, including the absence of sludging of the developer.

Abstract: A thermal lithographic printing plate, which can be imaged by thermal energy typically by imagewise exposure with an infrared emitting laser, a thermal printing head, etc., is made up of a hydrophilic substrate, and a composite layer structure composed of two layer coatings. Preferably, the first layer of the composite is composed of an aqueous developable polymer mixture containing a solubility inhibiting material and a photothermal conversion material which is contiguous to the hydrophilic substrate. The second layer of the composite is insoluble in the aqueous solution, is ink receptive, and is composed of one or more non-aqueous soluble polymers which are soluble or dispersible in a solvent which does not dissolve the first layer. The plate is exposed with an infrared laser or a thermal print head, and upon aqueous development of the imaged plate, the exposed portions are removed exposing hydrophilic substrate surfaces receptive to conventional aqueous fountain solutions.

Abstract: A method for producing a predetermined resist pattern on e.g. a lithographic printing plate, circuit board or mask, comprises the patternwise exposure to heat of a composition which comprises a novolac resin, a latent Bronsted acid and optionally a pigment. The composition is rendered preferentially soluble to a developer, in the regions which were heated.

Abstract: A thermal lithographic printing plate, which can be imaged by thermal energy typically by imagewise exposure with an infrared emitting laser, a thermal printing head, etc., is made up of a hydrophilic substrate, and a composite layer structure composed of two layer coatings. Preferably, the first layer of the composite is composed of an aqueous developable polymer mixture containing a photothermal conversion material which is contiguous to the hydrophilic substrate. The second layer of the composite is composed of one or more non-aqueous soluble polymers which are soluble or dispersible in a solvent which does not dissolve the first layer. The plate is exposed with an infrared laser or a thermal print head, and upon aqueous development of the imaged plate, the exposed portions are removed exposing hydrophilic substrate surfaces receptive to conventional aqueous fountain solutions. The unexposed portions contain the ink-receptive image areas.

Abstract: A lithographic imaging member is prepared by applying an ink jetable fluid to a fluid-receiving element that includes a clay-containing fluid-receiving surface layer. This layer also includes a water-soluble binder and a silane hardening agent. The applied fluid is an aqueous solution of a silane having multiple hydroxy, alkoxy or acetoxy groups that is readily absorbed in the clay-containing surface, and dried to provide an oleophilic image.

Abstract: A positive image can be obtained from a positive-working element that is sensitive to infrared radiation. The element comprises an imaging layer containing an alkali-soluble reactive resin (such as a phenolic resin), an infrared radiation absorbing compound, a thermochemical acid generating compound, and a dissolution inhibitor that has acid-cleavable C—O—C groups. Upon laser exposure, a Bronsted acid is generated which then breaks the bonds of the C—O—C groups, allowing the exposed regions of the reactive resin to be solubilized in an alkaline developer solution.

Abstract: The present invention relates to IR-sensitive compositions containing an initiator system comprising: (a) at least one compound capable of absorbing IR light (b) at least one compound capable of producing radicals and (c) at least one polycarboxylic acid comprising an aromatic moiety substituted with a heteroatom selected from N, O and S and also at least two carboxyl groups wherein at least one of the carboxyl groups is bonded to the heteroatom via a methylene group. These compositions are inter alia extraordinarily suitable for the manufacture of printing plates.

Abstract: A method for preparing a printing form and a method of printing are disclosed. A coating of a radiation sensitive ink on a lithographic support having a hydrophilic surface is imaged. The unexposed areas of the coating are removed to produce a printing form, which is used for printing. Preferably, the same radiation sensitive ink is used for printing as is used in the coating, and, preferably, the desired printing run length is predetermined and the thickness of the coating determined according to the desired run length.

Abstract: A heat imagable article has, in a single layer polymeric coating or in an inner layer of a multi-layer polymeric coating on a substrate, a polymeric matrix material, for example a phenolic resin, and, dispersed therein, polymeric particles, for example of polyethylene or polytetrafluoroethylene. The coating may contain a radiation absorbing compound so that suitable electromagnetic radiation, preferably infra-red radiation, may be used to heat the coating imagewise. The presence of the particles increases the physical robustness of the layer.

Abstract: An imagable composition, for example a coating on a lithographic printing plate, comprises a carboxylic acid derivative of a cellulosic polymer and a diazide moiety, and may be imaged in various ways, including by ultra-violet radiation, by infra-red radiation and by heat. The presence of the cellulosic polymer can act to enhance resistance to certain organic liquids and/or to increase operating speed.

Abstract: The invention relates to the use of cationic latex particles that can complex with anionic dyes to provide water fastness and further to provide a medium in which inherently unstable anionic dyes can be brought in close proximity with other anionic components, by complexation to cationic latices, in order to stabilize the anionic dyes especially with regard to light and oxidative degradation. In particular this invention will provide for methods of generating waterfast and improved lightfast ink jet images.