| 摘要 |
PURPOSE:To obtain a composition superior in color developing sensitivity, to UV rays, and resistance to color development on exposure to visible light and heat in the case of fixing, by adding aryl diazonium salt for producing Lewis acid upon exposure to UV rays, and a leuco dye for developing color by action of Lewis acid. CONSTITUTION:Aryl diazonium salt (component a) producing a Lewis acid, such as ZnCl2 or BF3 upon exposure to UV rays; a leuco dye developing color by action of the Lewis acid (component b); a quinone photoreducing agent producing a reducing agent in presence of a hydrogen donor, such as polyethylene glycol, upon exposure to visible light (component c); a hydrogen donor, such as polyethylene glycol, providing active H to said reducing agent (c) upon exposure to visible light (component d); and a Co (III) complex reacting with said produced reducing agent in a rate increased by heating, and producing NH3, amine, or the like suppressing the action of the Lewis acid are in corporated in a photothermosensitive composition. A support is coated with this composition to obtain an image recording meterial. Use of thd component (a) permits said composition to be enhanced in sensitivity to UV rays, and good in fixing sensitivity, and reduced in price. |
