lithopone powder pricelist suppliers

Titanium dioxide factories are state-of-the-art establishments, equipped with cutting-edge technology and stringent quality control measures. These facilities specialize in the extraction and refinement of titanium dioxide from raw materials like ilmenite, rutile, or anatase. The process, known as the sulfate or chloride route, involves several stages including digestion, precipitation, calcination, and finally, milling to achieve the desired particle size and optical properties.

...

The first commercial production of TiO2 began in the early 20th century, using the sulfate process. This method involved reacting ilmenite ore with sulfuric acid to produce titanium sulfate, which was then calcined to obtain titanium dioxide. However, this process had several drawbacks, including high energy consumption, generation of large amounts of waste, and release of harmful gases such as sulfur dioxide. As a result, many factories transitioned to the chloride process, which offers higher purity TiO2 and reduced environmental impact.

...

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 the pigment itself can vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant may be used, such as a 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.

...