PAINT THAT GLOWS

Wairarapa Times-Age, 29 May 1942, Page 4

PAINT THAT GLOWS

EXPERIMENTAL USE IN LONDON. POSSIBLE EXTENSIONS. A paint that glows in the dark is being used for showing up objects in London’s black-out, and it foreshadows germless houses in the future. To “activate” the paint, ultra-violet rays generated by specially filtered filament lamps are thrown upon it, when the object painted gives out a bluish glow and becomes visible in the dark. The system is being experimented. with by London’s Underground system, and, in the entrances to four stations in London's West End, stairrisers, bull's eye signs and indication strips have been treated, and further tests are being carried out at a trolleybus depot where a track will be treated to guide the trolley-buses into the depot. The, principle of “fluorescence,” or the generation of light by any substance under ultraviolet rays,' was discovered by an Englishman, Sir John Herschel, one hundred years ago.

Its war time application may lead to its extensive use in painting the walls of rooms with fluorescent paint, which, when activated gives off light approximately three times more effective than filament lighting. It can be so arranged that the wave-length of the exciting light not alone causes the paint to fluoresce kills off bacteria in the atmosphere. If the present black-out experiments prove successful, the fluorescent paint will be made use of in a variety of ways, for example by illuminating the platform steps of buses, edges of railway station platforms, and tramway, junctions. Already many private business houses have installed the system for lighting entrance halls where the street doors have to be opened in the black-out.