METHOD OF PREPARING LIGHT SENSITIVE MATERIAL Russian patent published in 1998 - IPC

FIELD: light sensitive materials. SUBSTANCE: material is prepared from a lead salt and sodium thiosulfate to give light sensitive layer composition, which is applied onto carrier. In order to decrease level of color fog on the image, lead acetate is used as lead salt and light sensitive layer composition is prepared by mixing lead acetate and sodium thiosulfate solutions at 1:1 molar ratio to form lead thiosulfate precipitate, which is then treated by sodium thiosulfate solution in quantity 2-10 mol per 1 mol of original lead acetate. To further increase light sensitivity of material, 0.05 to 0.2 mol urea is additionally introduced into reaction space after sodium thiosulfate- mediated dissolution of lead thiosulfate is completed. EFFECT: increased light sensitivity.