Fine‐Tuning: Advances in Chlorine‐Free Blue‐Light‐Generating Pyrotechnics

One of the most challenging tasks in the field of light‐producing pyrotechnics is the generation of saturated blue light with high spectral purity. Only copper salts in combination with chlorine seem to be high‐performing blue light emitters. However, in modern pyrotechnics the application of chlorine should be avoided. Different strategies are presented to further fine‐tune literature‐known chlorine‐free blue‐light‐emitting pyrotechnical compositions. The copper iodate as well as the copper bromate systems have been studied by using small amounts of nitrogen‐rich compounds like 1,2,4‐triazole, 5‐amino‐1H‐tetrazole or 3‐nitro‐1H‐1,2,4‐triazole. To overcome sensitivity issues, a two‐component epoxy binder system was introduced. The application of both copper(I) iodide and copper(I) bromide in the same pyrotechnical formulation were considered as blue‐light‐emitting species. Further, a quite new approach by using copper(I) nitrogen‐rich coordination compounds was investigated to give a blue flame color. All relevant formulations were characterized with respect to their dominant wavelength and spectral purity as well as impact and friction sensitivity