| 摘要 |
1,248,235. Photographic silver halide materials. EASTMAN KODAK CO. Dec.10, 1968 [Dec.11, 1967], No.58598/68. Heading G2C. A sensitive photographic material comprises a support bearing a layer comprising a photographic silver halide containing occluded polyvalent metal ions, the material containing a halogen acceptor, by which is meant a compound which enhances the photolytic silver yield or the photolytic silver density of print-out silver in a photographic silver halide emulsion, and a stabilizer precursor (i.e. a compound which has negligible silver halide stabilizing activity, but which can be treated with an activator compound, such as a free base, and/or be heated to give an active stabilizer), incorporated in the silver halide - comprising layer or a layer adjacent thereto. The layer comprising the silver halide may be a photographic silver halide emulsion layer. The polyvalent metal ions may be the trivalent ions of arsenic, antimony, bismuth, rhodium, iridium and gold or the tetravalent ions of osmium, indium or platinum. The halogen acceptor preferably contains nitrogen and may be of the urazole type. The stabilizer precursor is preferably a thio compound having an alkyl group attached to the sulphur atom and many examples are given. In the examples a visible image is obtained with the sensitive photographic material of the present invention, the latter being first exposed imagewise, then preferably heated to 190 to 500‹F. (or contacted with basic solutions) to inhibit printing-out in the non-image areas and to activate the stabilizer precursor which improves the stability of the background areas to high humidity or moisture and to prolonged exposure to room light, and finally uniformly exposed to photo-develop the latent image produced by the first exposure. The material according to the present invention may apparently also function as a print-out material. |
