Abstract: A method of processing imageable elements useful as alkaline-developable lithographic printing plate precursors that does not require either a rinsing step or a further gumming step is disclosed. The method comprises simultaneously developing and gumming the imaged element with an aqueous alkaline developing-gumming solution comprising one or more water-soluble polyhydroxy compounds of the following structure: R1(CHOH)nR2 in which n is 4 to 7; and either (i) R1 is hydrogen, aryl, or CH2OH; and R2 is hydrogen, alkyl group having 1 to 4 carbon atoms, CH2OR3 in which R3 is hydrogen or an alkyl group having 1 to 4 carbon atoms, CH2N(R4R5) in which R4 and R5 are each independently hydrogen or an alkyl group having 1 to 4 carbon atoms, or CO2H, or (ii) R1 and R2 together form a carbon—carbon single bond.

Abstract: Modeling spectral characteristics of an image acquisition device. In one implementation, a computer system predicts the spectral reflectance or transmittance of a sample scanned by an image acquisition device, such as a graphics arts scanner, by modeling the device. The sample is scanned by a scanner. The computer system searches for media coordinates in a colorant space corresponding to the sample. The media coordinates correspond to an estimated spectrum in a media model. The estimated spectrum generates estimated digital values through a forward model of the scanner. The estimated digital values are compared to target digital values generated by the scanner to calculate an error value. The computer system repeats this process until a desired stopping criterion or criteria are met. The estimated spectrum corresponding to the final estimated digital values represents the reflectance spectrum of the sample as scanned by the scanner.

Abstract: A lithographic printing plate precursor comprises a substrate, a free radical polymerizable photosensitive layer comprising a light-sensitive composition on the substrate, and a water-soluble overcoat layer on the photosensitive layer, wherein the overcoat layer comprises polyvinyl alcohol, and a further component that is not amphoteric and is poly(1-vinylimidazole) or a copolymer of 1-vinylimidazole and at least one further monomer. The photosensitive layer comprises a free radical polymerizable component and a photoinitiator.

Abstract: An aqueous developer for lithographic printing plates and a method for developing the printing plates are disclosed. The developer comprises an organic dispersing agent. The developer develops multi-layer printing plates quickly, with high throughput, but with no sludge formation in the developing process.

Abstract: A radiation-sensitive composition for use in printing plates is described. The composition comprises: (a) at least one novolak; (b) at least one naphthoquinone diazide derivative; and (c) a copolymer comprising units A, B, and a unit C comprising a cyclic terminal urea group, wherein unit A is present in an amount of about 5 to about 50 mol % and has the formula wherein R1 is selected such that the homopolymer of A is alkali-soluble, unit B is present in an amount of about 20 to about 70 mol % and has the following formula wherein R2 is selected such that the homopolymer of B has a glass transition temperature greater than 100° C., preferably a glass transition temperature in the range from about 100 to about 380° C.

Abstract: An aqueous alkaline developing system for alkaline-developable lithographic printing plates and a method for its use are disclosed. The developing system comprises one or more water-soluble suppressors of the following structure: R1(CHOH)nR2 in which: n is 4 to 7; and either (i) R1 is hydrogen, aryl, or CH2OH; and R2 is alkyl group having 1 to 4 carbon atoms, CH2OR3 in which R3 is an alkyl group having 1 to 4 carbon atoms, CH2N(R4R5) in which R4 and R5 are each independently hydrogen or an alkyl group having 1 to 4 carbon atoms, or CO2H; or (ii) R1 and R2 together form a carbon—carbon single bond. The developing system is especially suited for developing imageable elements useful as lithographic printing plates. The developing system is especially suited for use with elements in which (1) the imageable layer comprises at least one phenolic resin or at least one polymeric compound having pendent sulfonamide groups, and (2) the substrate is aluminum or and an aluminum alloy.

Abstract: Several optical heads are mounted on a common carriage adapted to scan a photosensitive printing plate. Each head is equipped with a laser source, a modulator and projection optics and can project a segment containing a plurality of pixels. The optical track of beams in each head is folded several times in such a way as to reduce the width of the head as well as its height. When the carriage moves from one edge of the plate to the other edge a swath of pixels is projected. Each head includes means to adjust the width, location, orientation and intensity of the segment it generates. Each head is accurately positioned on the carriage so that at least two abutting swaths are projected during each sweep of the carriage to produce a wider swath.

Abstract: A precursor that may be imaged by heat is made up of a substrate, for example a copper board, and a composite layer structure composed of two layers. Preferably, the first layer is composed of an aqueous developable polymer mixture containing a photothermal conversion material, which is contiguous to the 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 precursor is exposed with an infrared laser or a thermal print head, and upon aqueous development, the exposed regions are removed, revealing regions of the substrate surface able to be etched or otherwise treated. The second layer may also contain a photothermal conversion material. Alternatively, the composite layer may be free of photothermal conversion material when thermal imaging is carried out using a thermal print head. The precursor may be used, for example, as a mask precursor or electronic part precursor.

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.

Abstract: The present invention provides a positive working imageable composition, which includes a hydroxyfunctional resin comprising a covalently bound radiation sensitive group capable of increasing the solubility of the imageable composition in an alkaline developer upon exposure to radiation; and an isocyanate crosslinking agent. The present invention further provides an imageable element, which includes a substrate and an imageable composition according to the present invention coated on a surface of the substrate and a method of producing an imaged element according to the present invention. Also provided is a radiation sensitive hydroxyfunctional resin including a covalently bound radiation sensitive group capable of increasing solubility in an alkaline developer of an imageable composition derived therefrom upon exposure of the imageable composition to radiation.

Abstract: Predicting a reflectance spectrum of a photographic print based on data from a scanned color negative. The technique uses dye concentration, providing a channel-independent basis for the spectral model. The spectral model includes three conceptual sections: scanner and film models, a photographic printer model, and a photographic paper model. The scanner and film section converts digital data from a scan of a color negative on a calibrated scanner into predictions of the spectral transmittance for each pixel. The photographic printer section uses an exposure schedule and optionally a color temperature and computes the spectrum of the exposing illumination as a function of time. The photographic paper section converts the illuminated negative's spectral power first into dye concentration estimates and subsequently into a predicted reflectance spectrum for the simulated print.

Abstract: Imageable precursors for masks and for electronic parts comprise a polymeric layer applied to a substrate. The layer comprises at least one polymer having infra-red absorbing groups carried as pendent groups on the polymer backbone. Certain infrared absorbing groups may also act to insolubilize the polymer in a developer, until it is imagewise exposed to infra-red radiation. Imagewise application of heat, resulting from imagewise exposure of the precursor to infra-red radiation, renders the polymer layer more soluble in the developer than prior to exposure to the infra-red radiation.

Abstract: The present invention relates to a lithographic printing plate in which images can be inscribed by laser beams, and which has high resolving power, high sensitivity, and the improved reservation stability, and relates to its image-producing method, and a photosenstitive composition which can preferably be used as an original plate for lithographic printing. The photosenstitive composition includes an aqueous resin composition including fine particles (a) of a resin having at least one neutralized anionic group and having a heat fusion property, and a water soluble resin (b) having at least one neutralized anionic group, wherein the water soluble resin (b) is included in a range of 1 to 30% by weight, relative to the total weight of the aqueous resin composition; and a substance (c) which absorbs light and generates heat.

Abstract: The invention is directed to compensating for imaging aberrations that result from repeated passes by an imaging laser array. The aberrations may result from swath lines formed by thermal heating and from the ruling and screen angle of the image. The techniques described herein reduce the undesirable aberrations in thermal laser generated images by breaking up and/or reducing the swath lines. In general, the techniques provide for overlapping swaths and providing masking for one or both passes that print the overlapped region.

Abstract: A precursor for preparing a resist pattern comprises an imageable layer which includes a relatively volatile compound that can be volatilized by application of heat, wherein imaging radiation can be applied to the precursor to heat areas thereof and volatilizes said compound so that properties, for example, the ink accepting abilities of heated and non heated areas, are different.

Abstract: An improved method and apparatus for calibrating an imaging system having multiple imaging outputs such as a plurality of laser diodes. Calibration is achieved by driving each imaging output to form a test pattern on an imaging element, each test pattern having one or more image regions and each image region having a target optical property such as a target optical density. Next, an optical property, such as optical density, is measured for each image region. A response curve is generated for each set of image regions having substantially equal target optical properties. The imaging outputs are adjusted by reducing a difference between the measured optical property and the generated response curve, thereby reducing optical variations between regions that are imaged by the multiple imaging outputs.

Abstract: Infra-red absorbing polymers useful in imageable products and the lithographic printing field comprise infra-red absorbing groups carried as pendent groups on a polymer backbone. Certain infra-red absorbing groups may also act to insolublize the polymer in a developer, until it is imagewise exposed to infra-red radiation. The resulting heat renders the polymer soluble in the developer. Imageable products employing the infra-red absorbing polymers may include positive working lithographic printing plates.

Abstract: Positive-working imageable elements and methods for their preparation are disclosed. The elements comprise a hydrophilic substrate; a bottom layer, which contains a positive-working photosensitive composition; and a protective overlayer, which has an overlayer material that reduces the solubility of the photosensitive composition in an aqueous alkaline developer. The overlayer may be conveniently applied by a dip and rinse procedure.

Abstract: A direct-to-press imaging method comprises: (a) applying an imageable coating to a printing cylinder, wherein the imageable coating comprises a composition such as a thermally switchable polymer which changes affinity for a printing fluid upon exposure to imaging radiation such as infrared radiation delivered imagewise via a laser, and the imageable coating is substantially insoluble in the printing fluid; (b) imagewise exposing the imageable coating to actinic radiation to obtain an imaged coating; (c) printing a plurality of copies of an image from the imaged coating; and (d) reapplying the imageable coating as desired by repeating steps (a) through (c) at least once without substantially removing the prior imaged coating before reapplying the imageable coating.

Abstract: A method for imaging patterning compositions comprising the steps of: