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: 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: 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 negative-working image forming process which comprises the steps of:

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 precursor which 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: Imagable 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 infra-red 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: 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 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: An imagable article comprises a thermally imagable coating on a substrate, the coating comprising a radiation absorbing compound and a metal compound which is thermally decomposable, to form a metal. The imagable article is imagewise exposed to electromagnetic radiation, which is converted to heat by the radiation absorbing compound. The imaged article is then subjected to a developer, and in regions that have been exposed the thermally decomposable metal compound is decomposed to elemental metal, and regions that have not been exposed dissolve in the developer leaving behind the regions of elemental metal.

Abstract: Phenolic resin compositions formulated for use in lithographic exposure processes are given a heat treatment at 40-90° C. for at least 4 hours shortly after their coating onto lithographic substrates, to produce lithographic printing forms. It is found that such a heat treatment improves later exposure processes, in particular by rendering the sensitivity of the compositions 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 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 precursor for electronic parts, for example printed circuit boards, has a negative-working thermally-imagable layer on a substrate, for example a copper board or semiconductor. The layer comprises a cross-linking agent, a thermally-activated acid generator, and a polymeric substance containing polyvinylphenol units and alkyl acrylate units. Such as layer has improved mechanical properties with maintenance of good imaging properties.

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.