Abstract: A method of roughening a surface of a printing form precursor. The method comprises subjecting at least a part of the surface to energy in the form of pulses of electromagnetic radiation to produce a uniformly hydrophilic roughened surface on at least a part of the printing form precursor and optionally converting the uniformly hydrophilic roughened surface of the printing form precursor to a uniformly hydrophobic roughened surface. The method is useful for providing a surface for use in a subsequent imaging and/or printing process in lithographic printing. Methods of providing a printing form comprising an image formed of hydrophobic regions and hydrophilic regions using said method and a method of printing using said method are also described, as are printing forms so produced and imaging devices and apparatus for carrying out the said methods.

Abstract: A method of imaging printing plates uses a single imaging device having at least one laser delivering, in an imagewise manner, pulsed electromagnetic energy of pulse duration not greater than 1×10?6 seconds. Such an imaging method permits the imaging of a plurality of types of printing plates irrespective of any sensitised imaging chemistry contained in their coatings.

Abstract: A method of roughening a surface of a printing form precursor. The method comprises subjecting at least a part of the surface to energy in the form of pulses of electromagnetic radiation to produce a uniformly hydrophilic roughened surface on at least a part of the printing form precursor and optionally converting the uniformly hydrophilic roughened surface of the printing form precursor to a uniformly hydrophobic roughened surface. The method is useful for providing a surface for use in a subsequent imaging and/or printing process in lithographic printing. Methods of providing a printing form comprising an image formed of hydrophobic regions and hydrophilic regions using said method and a method of printing using said method are also described, as are printing forms so produced and imaging devices and apparatus for carrying out the said methods.

Abstract: A method of preparing a printing form precursor for printing, or a printed circuit board precursor or a semiconductor precursor, the method comprising the step of applying electromagnetic radiation having a pulse duration of not greater than 1×10?6 seconds, in an imagewise manner, to an imagable surface of the precursor. The imaging process may cause ablation of the coating of the precursor or permit its development in a developer. In each case the imaging radiation needs not be tuned to imaging chemistry (if any) present in the coating. Alternatively the imaging process may induce a change of hydrophilicity or hydrophobicity, or other change of state, of an uncoated substrate.

Abstract: A method of preparing a printing form precursor for printing, or a printed circuit board precursor or a semiconductor precursor, the method comprising the step of applying electromagnetic radiation having a pulse duration of not greater than 1×10?6 seconds, in an imagewise manner, to an imagable surface of the precursor. The imaging process may cause ablation of the coating of the precursor or permit its development in a developer. In each case the imaging radiation needs not be tuned to imaging chemistry (if any) present in the coating. Alternatively the imaging process may induce a change of hydrophilicity or hydrophobicity, or other change of state, of an uncoated substrate.

Abstract: A method of preparing a printing form precursor for printing, or a printed circuit board precursor or a semiconductor precursor, the method comprising the step of applying electromagnetic radiation having a pulse duration of not greater than 1×10?6 seconds, in an imagewise manner, to an imagable surface of the precursor. The imaging process may cause ablation of the coating of the precursor or permit its development in a developer. In each case the imaging radiation needs not be tuned to imaging chemistry (if any) present in the coating. Alternatively the imaging process may induce a change of hydrophilicity or hydrophobicity, or other change of state, of an uncoated substrate.

Abstract: A printing form precursor comprises a printing surface which comprises an inorganic metal compound, the printing surface being hydrophobic and capable of being made hydrophilic by energy but capable of becoming hydrophobic again, for reuse, if desired. An associated method of printing includes steps of subjecting the printing surface imagewise to energy so as to locally increase its hydrophilicity sufficient to make the surface differentiated in its acceptance of an oleophilic a printing ink; applying the ink to the printing surface and printing from the printing surface; causing or allowing the printing surface to undergo a reduction in hydrophilicity sufficient again to make the printing surface uniform in its acceptance of a printing ink; and, if wished, repeating these steps on multiple occasions. Thus the invention achieves the goal of providing a printing form precursor which does not need a chemical developer, and which can be used multiple times, to print different images.

Abstract: A method of imaging printing plates uses a single imaging device having at least one laser delivering, in an imagewise manner, pulsed electromagnetic energy of pulse duration not greater than 1×10?6 seconds. Such an imaging method permits the imaging of a plurality of types of printing plates irrespective of any sensitised imaging chemistry contained in their coatings.

Abstract: A printing form precursor comprises a printing surface which comprises an anodic layer which is hydrophobic and capable of being made hydrophilic by fast laser pulses but capable of becoming hydrophobic again, preferably for re-use, if desired. These changes are influenced by thickness of the anodic layer, and by alloying elements in the anodic layer. Benefit is gained also from using a darkly coloured anodic layer and by permitting the change from hydrophilic to hydrophobic to take place in a carbonaceous or siliceous atmosphere. By such means the invention achieves the goal of providing a printing form precursor which does not need a chemical developer, and which can be used multiple times, to print different images.

Abstract: A printing form precursor comprises a printing surface which comprises an inorganic metal compound, the printing surface being hydrophobic and capable of being made hydrophilic by energy but capable of becoming hydrophobic again, for reuse, if desired. An associated method of printing includes steps of subjecting the printing surface imagewise to energy so as to locally increase its hydrophilicity sufficient to make the surface differentiated in its acceptance of an oxophilic a printing ink; applying the ink to the printing surface and printing from the printing surface; causing or allowing the printing surface to undergo a reduction in hydrophilicity sufficient again to make the printing surface uniform in its acceptance of a printing ink; and,if wished, repeating these steps on multiple occasions. Thus the invention achieves the goal of providing a printing form precursor which does not need a chemical developer, and which can be used multiple times, to print different images.

Abstract: A method of preparing a printing form precursor for printing, or a printed circuit board precursor or a semiconductor precursor, the method comprising the step of applying electromagnetic radiation having a pulse duration of not greater than 1×10?6 seconds, in an imagewise manner, to an imagable surface of the precursor. The imaging process may cause ablation of the coating of the precursor or permit its development in a developer. In each case the imaging radiation needs not be tuned to imaging chemistry (if any) present in the coating. Alternatively the imaging process may induce a change of hydrophilicity or hydrophobicity, or other change of state, of an uncoated substrate.

Abstract: A composition comprising a polymer which contains hydroxyl groups, the composition being suitable as a coating for an IR-imagable lithographic precursor, the composition comprising one or more agent(s) which: a) absorbs IR radiation of wavelength greater than 800 nm and consequently generates heat; b) functions as an insolubiliser which inhibits dissolution of non-imaged regions of the coating in a developer but permits dissolution of imaged regions during development; and c) improves the inhibition to dissolution of the non-imaged regions and/or the dissolution of the imaged regions so as to improve the dissolution contrast ratio (DCR) of the non-imaged/imaged regions; wherein the agent which performs function c) comprises a moiety which has hydrophobic and ionic character. Such a composition can show excellent selectivity as regards dissolution rates in developer, as between the imaged and non-imaged areas, whilst the energy needed to achieve this differentiation (or “operating speed”) is not comprised.

Abstract: A positive working printing form precursor comprises a thermally imagable composition which includes a hydroxyl group-containing polymer, for example a novolak resin. The composition has a weight of less than 1.1 gm?2. It has been found that using a low weight of the composition on the precursor improves the properties of the precursor, in particular by rendering the sensitivity of the precursor to imaging radiation less variable over time.

Abstract: A method of making a mask or an electronic part, for example a printed circuit, comprises the steps of delivering heat in a desired pattern to a precursor of the mask or electronic part, the precursor comprising a surface coated with a coating, the coating comprising a heat-sensitive composition itself comprising an aqueous developer soluble polymeric substance and a compound which reduces the aqueous developer solubility of the polymeric substance, wherein the aqueous developer solubility of the composition is not increased by incident UV radiation but is increased by the delivery of heat; then developing the precursor to remove the heat-sensitive composition in regions to which the heat was delivered. In the case of a printed circuit precursor the surface may be then etched in conventional manner to yield the required printed circuit.

Abstract: A positive working printing form precursor comprises a thermally imagable composition which includes a hydroxyl group-containing polymer, for example a novolak resin. The composition has a weight of less than 1.1 gm−2. It has been found that using a low weight of the composition on the precursor improves the properties of the precursor, in particular by rendering the sensitivity of the precursor to imaging radiation less variable over time.

Abstract: This invention is directed to a precursor for preparing a resist pattern by heat mode imaging, the precursor comprising a heat sensitive composition, the solubility of which in an aqueous alkaline developer is arranged to increase in heated areas, and a means for increasing the resistance of non-heated areas of the heat sensitive composition to dissolution in an aqueous alkaline developer (the “developer resistance means”), wherein said developer resistance means comprises one or more compounds selected from the group consisting of: (A) compounds which include a poly(alkylene oxide) unit; (B) siloxanes; and (C) esters, ethers and amides of polyhydric alcohols, wherein said heat-sensitive composition comprises an aqueous alkaline developer soluble polymeric substance (i.e. the “active polymer”) and a compound which reduces the aqueous alkaline developer solubility of the polymeric substance (i.e.

Abstract: A composition used as a resist in the manufacture of electronic parts, for example printed circuits, and which is rendered soluble in a developer by pattemwise delivery of heat, comprises a polymer and optionally an infrared absorbing compound. However in contrast to conventional compositions no compound is present which alters the solubility of the polymer in an aqueous developer.

Abstract: A method of making a mask or an electronic part, for example a printed circuit, comprises the steps of delivering heat in a desired pattern to a precursor of the mask or electronic part, the precursor comprising a surface coated with a coating, the coating comprising a heat-sensitive composition itself comprising an aqueous developer soluble polymeric substance and a compound which reduces the aqueous developer solubility of the polymeric substance, wherein the aqueous developer solubility of the composition is not increased by incident UV radiation but is increased by the said delivery of heat; then developing the precursor to remove heat-sensitive composition in regions to which the heat was delivered. In the case of a printed circuit precursor the surface may then be etched in conventional manner to yield the required printed circuit.

Abstract: A composition used as a resist in the manufacture of electronic parts, for example printed circuits, and which is rendered soluble in a developer by patternwise delivery of heat, comprises a polymer of general formula (I), wherein R1 represents a hydrogen atom or alkyl group, R2 represents a hydrogen atom or alkyl group, R3 represents a hydrogen atom or alkyl group, and R4 represents hydroxyalkyl group, and wherein the ratio n/m is in the range 10/1 to 1/10.

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,