| 摘要 |
PURPOSE:To form easily a clear image by simple operation, by using a sublimable leuco dye as a developing agent incorporated in a heat development type color photosensitive silver salt material. CONSTITUTION:The desired heat development type color photosensitive silver salt material is obtd. by incorporating a leuco dye represented by the formula (where each of R1 and R2 is lower alkyl, and X is phenyl or the like) into a layer other than an image receiving layer. The leuco dye is sublimed by heating to reduce imagewise Ag<+> in a photosensitive layer, and the dye itself is oxidized to form color. At the same time, the dye loses its sublimability. When the material is imagewise exposed and heated, the leuco dye 4 is sublimed and diffused in the photosensitive silver salt layer 2. In the exposed part A, Ag<+> is reduced by the dye 4 to form a silver image,the dye 4 itself is oxidized to form a color image, and the dye 4 loses its sublimability and stays in the layer 2. In the unexposed part B, the dye 4 passes through the layer 2 and reaches the image receiving layer 3, where it reacts with a coupler and forms color. |
