barium sulphate in paint

Rutile, the most common form of titanium dioxide, is a reddish-brown pigment with a high refractive index and excellent weathering resistance. It is mainly used in paints, coatings, plastics, and paper industries due to its ability to provide excellent whiteness, opacity, and UV protection. Rutile titanium dioxide is typically produced by the sulfate process, which involves the reaction of titanium ore with sulfuric acid to produce titanium sulfate. The resulting solution is then treated with ammonia to precipitate titanium hydroxide, which is subsequently calcined at high temperatures to obtain rutile titanium dioxide.

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While loose titanium dioxide presents a problem, titanium dioxide within sunscreen formulations presents a much safer option than conventional sunscreen chemicals like oxybenzone and octinoxate. However, titanium dioxide may become dangerous when it is nanoparticle size. Generally, nanoparticles can be 1000 times smaller than the width of a human hair. Despite nanoparticles becoming increasingly common across industries, they have not been properly assessed for human or environmental health effects, nor are they adequately regulated. Researchers don’t quite understand the impacts nanoparticles could have on human health and the environment. However, because of their infinitesimally small size, nanoparticles may be more chemically reactive and therefore more bioavailable, and may behave differently than larger particles of the same substance; these characteristics may lead to potential damage in the human body or ecosystem.

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