china titanium dioxide powder

For exterior wall paint materials, titanium dioxide plays a critical role in enhancing weather resistance. Its ultraviolet (UV) light absorption characteristics protect the binder system from degradation caused by sunlight exposure. As a result, paints containing titanium dioxide are less likely to fade, chalk, or crack under harsh environmental conditions. Moreover, its chemical stability prevents the pigment from reacting with other paint components, maintaining the integrity of the coating and extending its lifespan.

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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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Prof Maged Younes, Chair of EFSA’s expert Panel on Food Additives and Flavourings (FAF), said: “Taking into account all available scientific studies and data, the Panel concluded that titanium dioxide can no longer be considered safe as a food additive . A critical element in reaching this conclusion is that we could not exclude genotoxicity concerns after consumption of titanium dioxide particles. After oral ingestion, the absorption of titanium dioxide particles is low, however they can accumulate in the body”. 

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