china interior wall coating lithopone suppliers

Good whiteness titanium dioxide rutile is a critical component for coating factories due to its exceptional optical properties. The term good whiteness refers to the pigment's ability to reflect a broad spectrum of visible light, resulting in a bright, clean appearance. This characteristic is particularly important in applications where a uniform and consistent color is desired, such as in paints, plastics, and paper manufacturing.

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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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