Abstract: There is disclosed a composition, element, and process of imaging, wherein a polymeric binder is rendered photocrosslinkable by virtue of a photoresponsive source of amines, and by virtue of one or more carbonyl groups on the binder which react with said amines to form a carbinolamine.

Abstract: A heat bleachable material comprises (i) at least one hexaarylbiimidazole with (ii) at least one dye, especially an antihalation or filter dye, that is reactive with the product of the hexaarylbiimidazole formed upon heating the material to a temperature above about 90.degree. C. This provides a material that becomes at least 40% colorless within about 20 minutes, typically within about 30 seconds, upon heating to a temperature as described. The dye-containing material is especially useful for antihalation and filter purposes in a photographic element. The material can be a heat bleachable dye layer of a photothermographic element. The heat bleachable dye layer can also be useful in a thermographic element.

Abstract: A radiation-sensitive element is disclosed including a radiation-sensitive layer comprised of a cobalt(III)complex and a photoreductant. A process is disclosed in which the photoreductant is converted to a reducing agent by exposure to electromagnetic radiation longer than 300 nanometers. The reducing agent is then reacted with a cobalt(III)complex. Images can be recorded directly within the radiation-sensitive layer or in a separate image-recording element or layer by use of the residual cobalt(III)complex not exposed or one or more of the reaction products produced by exposure. By using the ammonia liberated from ammine ligand containing cobalt(III)complexes on exposure in combination with imagewise and uniform exposures, positive or negative images can be formed in diazo image-recording layers or elements associated with the radiation-sensitive layer. By the selection of amine-responsive reducing agent precursors, the amines released by the cobalt(III) complexes cause an amplified image.

Abstract: A radiation-sensitive element is disclosed including a radiation-sensitive layer comprised of a cobalt(III)complex and a photoreductant. A process is disclosed in which the photoreductant is converted to a reducing agent by exposure to electromagnetic radiation longer than 300 nanometers. The reducing agent is then reacted with a cobalt(III)complex. Images can be recorded directly within the radiation-sensitive layer or in a separate image-recording element or layer by use of the residual cobalt(III)complex not exposed or one or more of the reaction products produced by exposure. By using the ammonia liberated from ammine ligand-containing cobalt(III)complexes on exposure in combination with imagewise and uniform exposures, positive or negative images can be formed in diazo image-recording layers or elements associated with the radiation-sensitive layer.

Abstract: A photothermographic element can comprise a support and on the support or in the support an antihalation or filter component that comprises a heat bleachable material comprising (i) at least one hexaarylbiimidazole with (ii) at least one dye, especially an antihalation or filter dye, that is reactive with the product of the hexaarylbiimidazole formed upon heating the material to a temperature above about 90.degree. C. This provides an antihalation or filter material that becomes at least 40% colorless within about 20 minutes, typically within about 30 seconds, upon heating to a temperature as described. The antihalation or filter material can be a heat bleachable dye layer of a photothermographic element.

Abstract: An imaging system is provided wherein a blocked dye precursor is activated by an amine to an unblocked form which, in the presence of an inert cobalt (III) complex containing amine releasing ligands, undergoes a redox reaction to form a dye. The amine generated during the redox reaction causes further dye formation, giving increased speed.

Abstract: An imaging element and process wherein a tetrazolium cation, which is present in combination with a reducing anion as a salt, is imagewise exposed and reduced by the anion to form a formazan dye, without the need for a separate photoreductant. Stabilization of the resulting dye and fixing of the element can be achieved by the introduction into the element of a salt of a metal.