Disclosed are photothermographic constructions containing at least a plurality of light-sensitive layers which are separated by barrier layers composed of a polymer, e.g., ethyl cellulose and polyethylene terephthalate, having an energy activation of permeability (E.sub.p) of less than about 30 kJ/mole. The barrier layers must be substantially insoluble in the light sensitive layers and vice versa. Each light sensitive layer contains a nitrate salt, leuco dye, binder, and optionally, a photoinitiator. The photothermographic construction is capable of effectively reproducing full color images.