Abstract: Radiation sensitive elements comprising a thin radiation sensitive layer of an amorphous chalcogenide of arsenic adhering to a substrate are utilized in the production of latent images when exposed to a suitable form of radiation, the latent images being developed by utilizing the inability of radiation exposed arsenic chalcogenide to cause reduction of noble metal salts. Noble metal salts are thus decomposed by arsenic chalcogenide which has not been exposed to radiation to form a direct positive image which can subsequently be intensified by physical development and/or electroless deposition of metal possibly followed by electrolytic deposition of metal. The form of radiation employed is generally visible light and diverse procedures for producing direct positive images are disclosed.

Abstract: Process for preparing photographic materials yielding on imagewise exposure to radiation a direct positive image is provided, which comprises the deposition of a thin layer of catalytically active metal onto a carrier base on the surface of which has been deposited an intermediate adhesive layer or surface filled by the deposition thereon and in direct contact therewith of a second thin layer of a photosensitive inorganic compound capable of reacting catalytically with the metal layer when activated upon exposure to radiation, so that the metal layer is destroyed on the illuminated areas but remains intact on the nonilluminated areas of the photographic material, creating in this way a direct positive metal image, capable of being stabilized and intensified.