We were recently asked about our UV Pens; what they can write on and if you can use the ink outdoors. Have you ever been to a club that stamps your hand with a UV stamp? It can take a little effort to wash off the ink. The UV ink in the pen is about as waterproof as that. It will endure a bit of rain but it won’t last for long. We don’t recommend leaving your UV writing exposed to the elements. Putting it inside a container is good. You can write on plastic, wood or metal. Remember though that even the inside of containers get get wet. For best results we recommend non-UV reactive, cold pressed, acid free paper with self sealing pouch.
You can see from the image above that this type of paper produces a much clearer result. White LED lights are not sufficient to get the ink to react. You will need a UV light source in order to see the ink.
We learned about using non-UV reactive paper from Avernar.