Abstract: A process is disclosed for the production of persistent phosphors, comprising exposing particles of phosphor precursors for a short time to a heat source selected from a particle plasma and an open flame arising from the combustion of hydrocarbons. A process for coating a substrate with persistent phosphors is also disclosed, comprising directing a stream of phosphor precursor particles for a short time through the same types of heat source toward the substrate. Preferred phosphors are Strontium Aluminate-based doped with Dysprosium and Europium.