| 摘要 |
1,159,856. Photographic silver halide materials. EASTMAN KODAK CO. Oct. 24, 1966 [Oct. 22, 1965], No.47704/66. Heading G2C. A photographic light-sensitive material comprises a transparent support bearing an internal latent image halogen acceptor - containing silver halide print-out layer and a silver halide developing-out layer. The print-out layer and developing-out layer are preferably on opposite sides of the support. The material is used in photo-mechanical drafting and may be exposed in different areas to successive light images, the visible print-out image formed on each exposure enabling subsequent images to be correctly positioned. When the succession of exposures is complete, the material is processed in a surface silver halide developer to develop the latent images formed in the developing-out layer and provide a stable developed image. The printout emulsion preferably contains a nitrogencontaining halogen acceptor e.g. tetrahydro- 1:3:5-triazine-4-thiol and the silver halide grains may have been formed in the presence of lead ions and a thioether silver halide solvent. The emulsion may also contain sodium anthraquinone- 2-sulphonate, formaldehyde and tartrazine yellow. The developing-out emulsion may contain tartrazine yellow, 5-nitroindazole as desenitizer, 4- hydroxy-6-methyl-1:2:3a:7-tetrazaindene and formaldehyde. |
