Glow in the Dark and UV Reactive Filament
How glow filament works
The glow comes from strontium aluminate pigment suspended in PLA. Charging the print under bright light (sunlight is best, an LED lamp works) loads energy into the pigment, which it re-emits as visible light over the next 30 minutes to several hours depending on the colour and the charge.
Colour options
- Glow green: brightest, longest hold, classic glow look
- Glow blue: dimmer than green, shorter hold
- Glow rainbow / multi: novelty colour shifts
- UV reactive: glows under blacklight, neutral under daylight
- Fluoro PLA: bright neon under any light, light UV reactivity
Print settings
Same as standard PLA: 200 to 220 C nozzle, 50 to 60 C bed. The pigment is mildly abrasive (similar to matte PLA). For one-off prints, a brass nozzle is fine. For repeat use, fit a hardened nozzle.
Charging the glow
- 5 to 10 minutes of direct sunlight gives the longest hold
- An LED room light for 15 to 30 minutes is usually enough
- UV flashlights charge the pigment fastest and brightest
- Glow brightness fades with print age; older prints still glow, just dimmer
Best uses
- Halloween decor and costumes
- Light switch surrounds, door handles, hallway markers
- Watch faces, jewellery, keychain charms
- Signage and emergency markers
- Tabletop minis and props with glow accents