The possibility of silver-triggered image enhancement using thermal energy transformed from Xenon-flash light was investigated to set up a technology which can stand clear of silver crisis. The photographic material has an imaging layer or layers containing silver halide emulsion with coating weight of approximately 0.1 g-Ag/m² and a thermally color-formable combination of a bisphenol and a leuco base. The silver halide works as the photo-sensor and the developed silver which itself has an extremely low density works as the trigger of heat-mode dye formation from the acid-base combination. The imaging process consists of imagewise exposure followed by black-and-white development and a uniform flash exposure of high intensity and short duration. The amplification as much as 10 times of the density available by conventional black-and-white development were obtained without any loss of photographic speed, but accompanied by a slight change of gradation. The experiment on the simplification of the imaging process indicated a possibility of semi-dry processing of 0.5 min.