china titanium dioxide manufacturer

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 Lithopone B301, Lithopone B311 powder itself may vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant might be used, like 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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Rutile, one of the two common natural forms of TiO2, possesses a tetragonal crystal structure that imparts it with superior chemical stability and excellent optical properties. Unlike its anatase counterpart, rutile TiO2 exhibits greater hardness and density, making it more resistant to discoloration and corrosion. This durability makes rutile particularly suitable for outdoor applications where exposure to environmental factors is inevitable.

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