rutile titanium dioxide r996 white pigment factory

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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The global barium sulfate market is subject to fluctuations due to changing economic conditions and environmental regulations. The increasing demand from the oil and gas sector, driven by drilling activities, has been a significant driver for barium sulfate production. However, the market is also influenced by the growth of the paint and coating industry, where barium sulfate is used as a to improve the opacity and durability of coatings.

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