Although barium sulfate is almost completely inert, zinc sulfide degrades upon exposure to UV light, leading to darkening of the pigment. The severity of this UV reaction is dependent on a combination of two factors; how much zinc sulfide makes up the pigments formulation, and its total accumulated UV exposure. Depending on these factors the pigment itself can vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant may be used, such as a small amount of cobalt salts, which would be added to the formulation. This process creates cobalt-doped zinc sulfide. The cobalt salts help to stabilize zinc sulfide so it will not have as severe a reaction to UV exposure.

About Titanium Dioxide. Titanium Dioxide, a white crystalline powder, represents the natural oxide of titanium, with its primary occurrence observed specifically in rutile ores. This titanium compound holds remarkable significance in various technological realms, functioning as a commodity chemical extensively harnessed across diverse industries. In actuality, a substantial majority of titanium ores undergo processing procedures to yield Titanium Dioxide, consequently establishing its unrivaled status as the most extensively utilized titanium-based substance on a global scale.