INFRARED-SENSITIZED SILVER HALIDE SYSTEMS

1347716 Infrared photography EASTMAN KODAK CO 28 May 1971 [20 July 1970] 17745/71 Heading G2C A photographic element comprises at least one supported internal image silver halide emulsion which contains an infrared sensitizing dye having an absorption peak in the infrared region and in which the silver halide grains contain at least one metal dopant. In the Examples, there are described I.R. sensitized emulsions which (A) are iridium, osmium, bismuth or rhodium cored emulsions, iridium doped emulsions, and core/shell emulsions in which the shell is sulphur and gold sensitized which are optionally hypersensitized with aqueous silver nitrate, surface sensitized with thiourea dioxide, and/or mixed with a triazine-stilbene brightening agent, or (B) are Bi doped and coated with dithiourazole/methylvinyl ether adduct. Emulsions (B) are exposed, heated and photo developed with U.V. The emulsions may be used in the silver salt diffusion transfer process.