this invention relates to a thermal dye transfer assemblage comprising : i ) a dye - donor element comprising a support having thereon a set of sequential repeating dye patches of two subtractive primary color image dyes dispersed in a polymeric binder ; and ii ) a dye - receiving element comprising a support having thereon in order : a ) a layer comprising a heat - sensitive , dye - forming precursor of a third , complementary , subtractive primary color image dye dispersed in a polymeric binder , the dye - forming precursor being capable of forming the third , complementary , subtractive primary color image dye at a temperature which is higher than the temperature used to transfer the other two subtractive primary color image dyes ; and b ) a dye image - receiving layer ; the dye - receiving element being in superposed relationship with the dye - donor element so that the dye layer is in contact with the dye image - receiving layer .