... last more than 20 hours. Upon removal of the light source, the stored light is gradually released, the strongest glow is produced ... it fades over a period of time, when there is light again, it stores energy again. So the photoluminescence process is ... plastic:1. This new type of luminous powder of is compatible with acrylic, polyester, epoxy, PVC, polypropylene and polyethylene (HDPE, LDPE etc ...