The EU project SESBE is developing inorganic Transparent Conductive Oxide (TCO) coatings, based on metal oxides, to reduce the risk of fire propagation for e.g. building façade materials. Thin layers of indium tin oxide or zinc oxide have been shown to delay ignition times of PMMA (poly(methyl methylacrylate) = “plexiglass”) when the coated materials are exposed to thermal radiation (25 kW/m2).
The thin inorganic layers are transparent to visible light, so do not deteriorate the material’s appearance, but reflect long-wave radiation (heat), whereas standard paints absorb up to 90% of heat radiation. The use of such coatings could reduce emitted heat from a burning façade and could delay or prevent ignition of the treated façade materials in case of a nearby fire.
SP Sweden “Brandposten” n°52 (2015) http://www.sp.se/en/units/fire/brandposten/Sidor/default.aspx