Abstract: A heat-developable image-recording material comprising an organic silver salt, a reducing agent, and an organic binder, wherein the material further comprises a compound represented by the following formula (I) or (II): wherein R1 is a group selected from the group consisting of hydrogen atom, an alkyl group, an aryl group, hydroxyl group, amino group, thiol group, an alkoxyl group, and thioether group; and R2 and R3 may be the same or different and represent hydrogen atom or 1 to 4 functional groups.

Abstract: After copper of printed circuit board lined with copper foil is etched with an acidic etching solution containing chloride ions, the resulting etching solution containing copper ions is placed in a cathode compartment partitioned with a diaphram from an anode compartment, while placing a caustic soda solution in the anode compartment, and subjected to electrolysis. In the cathode compartment, copper is deposited on an electrode without any redissolution of the deposited copper, and recovered, whereas in the anode compartment chlorine formed on an anode is absorbed into the caustic soda solution without any discharge to the atmosphere. The etching solution thus freed from the copper ions is admixed with the same kind of chemicals as consumed by the etching, and used again as a regenerated etching solution.

Abstract: An image-receiving material for silver salt diffusion transfer process having at least two layers wherein (I) a polymer layer containing diffusible compound, which can change the property of silver image formed in a binder layer containing silver deposition nuclei, and (II) the binder layer containing silver deposition nuclei on said polymer layer are provided on support, said polymer layer comprising at least one water insoluble hydrophilic polymer selected from the group consisting of homopolymers, copolymers and graft polymers of monoacrylates of polyhydric alcohols and homopolymers, copolymers and graft polymers of monomethacrylates of polyhydric alcohols.