uses lithopone suppliers

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.

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Suppliers play a crucial role in transforming these raw materials into usable titanium dioxide. They employ specialized extraction techniques such as the Becher process for ilmenite or the sulfate process for rutile and anatase, which involve chemically treating the ore to produce titanium dioxide. In the sulfate process, for example, the ore is treated with sulfuric acid to form titanyl sulfate, which is then calcined to yield titanium dioxide.

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