Photoluminescent prod. for use as safety device - giving improved photoluminescence compared with conventional phosphorescent prod.

摘要

A photoluminescent prod. contains (a) a binding agent of which the spectral response goes from the near ultra-violet to the infra-red with a max. coefft. of transmissibility of light; (b) crystalline fillers with high transmissibility of light in the same spectral region; (c) =1 phosphorescent substance; (d) =1 substance drawing energy from low wavelengths and re-emitting it at the level of the absorption spectrum of the ph osphorescent substance; (e) =1 fluorescent substance chosen to give a retained colour possibly different from that of the phosphorescent substance. Novelty is that diphenyloxazol is used as component (d). The photoluminescent prod. is used partic. as a security material for use in the dark, being efficient partic. at the moment when lighting is switched off.