Abstract: A thermally-responsive dispersant for an aqueous dispersion of positively- or negatively-charged or chargeable solid or liquid particulates, comprises a compound having an anchoring moiety linked to a thermally-responsive polymeric stabilizing moiety, other than a polyalkylene oxide, the polymeric moiety having a lower affinity for the surface than the anchoring group below the thermal transition temperature, the particulates being positively-charged or chargeable when the anchoring moiety contains an acid and/or hydroxy group and has a net acidity or neutrality and the particulates being negatively-charged or chargeable when the anchoring moiety has a basic group and has a net basicity, wherein the dispersion exhibits a change in sign from negative to positive and an increase in magnitude of a rheological property (viscosity at low shear and/or complex modulus at low amplitude oscillatory shear), on increasing the temperature from below to above the thermal transition temperature.

Abstract: The invention provides an aqueous inkjet ink composition comprises a polymeric compound comprising discrete particles responsive to an external stimulus, and a functional material, wherein the functional material may be incorporated as part of the polymeric particles, the particles causing the composition to have a first rheological state and a different second rheological state in response to a stimulated change in conditions, the first rheological state being associated with a first lower viscosity of the composition, wherein the particles have a first lower volume, enabling the composition to pass through an inkjet printhead orifice and the second rheological state being associated with a second higher viscosity of the composition, wherein the particles have a second higher volume, enabling immobilisation of droplets of the composition on a substrate.

Abstract: The invention provides a dispersant for an aqueous dispersion of negatively charged or chargeable solid particulates which comprises a compound having an anchoring moiety linked to a polymeric hydrophilic moiety, the anchoring moiety containing at least one basic group and having an overall basicity and the polymeric moiety having a lower affinity for the particulate surface than the anchoring moiety. The invention also provides a coating composition containing the dispersant, an inkjet recording element containing the dispersant and methods of coating or reducing viscosity using the dispersant.

Abstract: The invention provides a dispersant for an aqueous dispersion of positively charged or chargeable solid particulates which comprises a compound having an anchoring moiety linked to a polymeric hydrophilic moiety, the anchoring moiety containing at least one acid and/or hydroxy group and having an overall acidity or neutrality and the polymeric moiety having a lower affinity for the particulate surface than the anchoring moiety. The anchoring moiety preferably contains at least two acid groups, preferably carboxylic acid groups, attached either in a [1,1], [1,2] or [1,3] relationship and is linked to the polymeric moiety, which is preferably derived from acrylamide or methacrylamide monomer units, preferably by a sulfur atom. The dispersant can reduce the viscosity of an aqueous dispersion of positively charged or chargeable solid particulates and can reduce the tendency of the resulting dispersion to form a gel or a yield stress material.

Abstract: The invention provides a coating composition containing boehmite particles and a dispersant which comprises a compound having an anchoring moiety linked to a polymeric hydrophilic moiety, the anchoring moiety containing at least one acid and/or hydroxy group and having overall acidity or neutrality and the polymeric moiety having a lower affinity for a boehmite surface than the anchoring moiety. The anchoring moiety preferably contains at least two acid groups, preferably carboxylic acid groups, attached either in a [1,1], [1,2] or [1,3] relationship and is linked to the polymeric moiety, which is preferably derived from acrylamide or methacrylamide monomer units, preferably by a sulfur atom. The dispersant can reduce the viscosity of the boehmite dispersion and the tendency of the boehmite dispersion to increase in viscosity and/or form a gel or a yield stress material following periods of high shear stress.

Abstract: A thermally-responsive dispersant for an aqueous dispersion of positively- or negatively-charged or chargeable solid or liquid particulate, comprises a compound having an anchoring moiety linked to a thermally-responsive polymeric stabilizing moiety, other than a polyalkylene oxide, the polymeric moiety having a lower affinity for the surface than the anchoring group below the thermal transition temperature, the particulates being positively-charged or chargeable when the anchoring moiety contains an acid and/or hydroxy group and has a net acidity or neutrality and the particulates being negatively-charged or chargeable when the anchoring moiety has a basic group and has a net basicity, wherein the dispersion exhibits a change in sign from negative to positive and an increase in magnitude of a rheological property (viscosity at low shear and/or complex modulus at low amplitude oscillatory shear), on increasing the temperature from below to above the thermal transition temperature.

Abstract: The invention provides an aqueous inkjet ink composition comprises a polymeric compound comprising discrete particles responsive to an external stimulus, and a functional material, wherein the functional material may be incorporated as part of the polymeric particles, the particles causing the composition to have a first rheological state and a different second rheological state in response to a stimulated change in conditions, the first rheological state being associated with a first lower viscosity of the composition, wherein the particles have a first lower volume, enabling the composition to pass through an inkjet printhead orifice and the second rheological state being associated with a second higher viscosity of the composition, wherein the particles have a second higher volume, enabling immobilisation of droplets of the composition on a substrate.

Abstract: The invention provides a dispersant for an aqueous dispersion of negatively charged or chargeable solid particulates which comprises a compound having an anchoring moiety linked to a polymeric hydrophilic moiety, the anchoring moiety containing at least one basic group and having an overall basicity and the polymeric moiety having a lower affinity for the particulate surface than the anchoring moiety. The invention also provides a coating composition containing the dispersant, an inkjet recording element containing the dispersant and methods of coating or reducing viscosity using the dispersant.

Abstract: The invention provides a dispersant for an aqueous dispersion of positively charged or chargeable solid particulates which comprises a compound having an anchoring moiety linked to a polymeric hydrophilic moiety, the anchoring moiety containing at least one acid and/or hydroxy group and having an overall acidity or neutrality and the polymeric moiety having a lower affinity for the particulate surface than the anchoring moiety. The anchoring moiety preferably contains at least two acid groups, preferably carboxylic acid groups, attached either in a [1,1], [1,2] or [1,3] relationship and is linked to the polymeric moiety, which is preferably derived from acrylamide or methacrylamide monomer units, preferably by a sulfur atom. The dispersant can reduce the viscosity of an aqueous dispersion of positively charged or chargeable solid particulates and can reduce the tendency of the resulting dispersion to form a gel or a yield stress material.

Abstract: The incorporation of coupler chemistry into the fluorescent element results in a greatly improved fluorescence imaging element, displaying higher photographic speed, higher contrast, and improved image discrimination. The coupler chemistry comprises the combination of a developing agent that generates an oxidized form on reaction with exposed silver halide, together with a molecule capable of forming a stable reaction product, preferably a dye, by reaction with the oxidized form of the developer. This will have the effect of a sink for oxidized developer formed during development. In a preferred embodiment, dye-forming chemistry is combined with fluorescent imaging to provide dramatic improvements in performance of the fluorescent system.

Abstract: The present invention is directed to a photothermographic imaging element comprising at least one silver halide imaging layer containing a fluorophore. The imaging element can be exposed and then processed by heating to form an image in which the intensity of the fluorescence from the element is modulated imagewise to yield a fluorescent image of the light intensities to which the element was exposed. The present invention is also directed to a method of processing photothermographic film that has been imagewise exposed in a camera, which method in order comprises thermally developing the film step without any externally applied developing agent, comprising heating said film to a temperature greater than 80° C.