LUMENTIFY
The core: storing light or converting light
All the materials described here glow because they have previously absorbed light. The difference lies in when they release it again:
- Phosphorescence – the material stores the light energy and releases it slowly after the light source is switched off. It glows in the dark.
- Fluorescence – the material converts light, such as UV, immediately into visible light. It only glows while it is illuminated and goes out immediately when the light source is switched off.
Our pigments do both
Glow pigments based on europium/dysprosium-doped strontium aluminate are phosphorescent and fluorescent. Under UV or black light they therefore glow particularly intensely while being irradiated – and after switching off they keep glowing. This is exactly the change shown by the "UV lamp" switch at the top of our pages.
The key terms
| Term | Meaning |
|---|---|
| Photoluminescence | umbrella term: glowing after excitation by light. Includes phosphorescence and fluorescence. |
| Phosphorescent | stores light and glows in the dark |
| Glow in the dark / afterglow | everyday terms for phosphorescent; in German "nachleuchtend" |
| Fluorescent | glows only during excitation, for example under black light |
| Daylight fluorescent / neon colour | looks particularly bright by day but does not glow in the dark |
| Daylight colour | what a glow pigment looks like in daylight – e.g. whitish, with a slight tint or strongly coloured |
| Glow colour | the colour of the afterglow in the dark – e.g. natural green, blue-green, blue |
| Charging / excitation | exposing the pigment to light so that it stores energy |
| Shimmer phase | the long, weaker phase of the afterglow after the first one to two hours |
| Doping | targeted addition of small amounts of other elements – in our case europium and dysprosium in strontium aluminate |
| SiO₂ coating | silicon dioxide shell around the pigment grains; makes them hydrolysis-resistant |
| Particle size | size of the pigment particles, given in µm (micrometres); ours range from 1 to 150 µm |
Watch out for confusion"Daylight fluorescent" and "neon" colours are fluorescent – they look vivid in daylight but do not glow in the dark. If you need an afterglow, ask for phosphorescent or glow-in-the-dark pigments.
What afterglow is not
Glow pigments need no energy source of their own: they only release the light they have previously stored. They are therefore not a light source and do not replace lighting – they make markings, edges and routes visible in the dark.