Photochromic Yellow Pigment
You can see more about these pigments by clicking here.
Changes color with exposure to UV light
Blue Wool Index = 1 (400,000 Lux-Hours)
Shelf Life approximately 12 months. Keep pigment in the dark when not in use.
Particle size average 4 microns
No solubility but you can mix with a variety of clear coats, varnishes, etc.