We have had the ability to make some things glow in the dark but recently we have been doing it differently. The supplier of the pigment recommends putting it on as a coating over the design and then the lighter areas glow but it was a bit restrictive and gave mixed results. What we are now doing is making headphones white, then coating them in glow in the dark pigment then building the design up on top masking off the white areas we want to keep glow in the dark and using transparrent paint where we want it to glow through a little this is letting us do designs that look sharper when they glow.
I foolishly sent these ones out without taking a picture of them in the dark but …. you can imagine they were awesome