Abstract: The present invention is directed to a heat-sensitive imaging material that comprises a support on which is formed a heat-sensitive imaging layer. This imaging layer comprises a color-forming amount of a substantially colorless, finally divided noble metal salt of an organic acid, an organic reducing agent that is capable of a color-forming reaction with the noble metal salt under heating conditions to produce a colored image, and a stabilizer compound of formula (I) that mitigates the formation of non-imaging background color in the imaging layer: ##STR1## In formula (I), Z.sub.1, Z.sub.2, and Z.sub.3 each independently represents hydrogen, an alkali metal ion, an alkyl group comprising 1 to about 8 carbon atoms, an aralkyl or cycloalkyl group comprising 5 to about 10 carbon atoms, or an aryl group comprising 6 to about 15 carbon atoms; or Z.sub.1 and Z.sub.