| abstract |
A composition is described comprising at least two co-crystallized acetylenic compounds, of different chemical structures, each containing at least one -C 3BOND C-C 3BOND C- group and substituents selected from the group consisting of sulfonate, urethane and alcohol radicals, at least one of the compounds capable of undergoing a contrasting color change upon exposure to actinic radiation or thermal annealing, wherein the composition exhibits a substantially different thermogram than the sum of thermograms of the individual components as obtained by differential scanning calorimetry. A device is also described useful for measuring the time-temperature or radiation-dosage history of an article comprising a substrate having deposited thereon the described composition. A process is also described for producing the composition of this invention. |