lithopone for leather manufacturer

Manufacturers of rutile titanium dioxide employ different processes to produce this versatile pigment. The two primary methods are the sulfate process and the chloride process. In the sulfate process, ilmenite ore is treated with sulfuric acid to form titanyl sulfate solution, which is subsequently processed into titanium dioxide. This method typically results in a more opaque and durable pigment that is preferred in applications where weatherability is crucial. On the other hand, the chloride process involves treating rutile ore with chlorine gas to produce titanium tetrachloride, which is then refined and oxidized to form titanium dioxide. This method often yields a higher purity product suitable for applications requiring greater brightness and color stability.

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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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