titanium dioxide pigment manufacturers

To make up the batch of lithopone the solution containing the original 1050 pounds of barium sulphide and 856 pounds of titanium acid cake is added to sufiicient zinc sulphate solution of approximately 35 Baum at 60 Centigrade to completely precipitate all the BaS as zinc sulphide and barium sulphate so that the final precipitate contains a suspen-. sion of co-p'recipitated zinc sulphide barium sulphate intimately mixed with a suspension of titanium oxide. On the completion of the reaction, shown by the complete absence of either soluble zinc or barium in a filtered por-.

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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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The surge in demand for interior and exterior paints and use of plastic across various end-use industries drive the global Lithopone market. Lithopone white pigment is used in paints and coating systems that find applications in residential and industrial landscapes. Hence, as the construction & building sector flourishes, the demand for building and architectural materials such as paints and coatings will increase. This trend is conducive for the Lithopone market growth. In addition, white plastic materials are increasingly being used in consumer products. Developments in plastic forming technology is anticipated to indirectly boost plastic production, thus, increasing the demand for white pigments during the forecast period.

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