2. Particle Size The application often dictates the required particle size. Suppliers typically offer various grades of barium sulphate, categorized by their particle size distribution. For example, finer particle sizes are often favored in cosmetic applications, while coarser grades may be used in construction materials.

Lithopone is a white pigment (PW5) co-precipitated from solutions of zinc and barium salts according to the following reaction: 

Moreover, titanium dioxide is also used in rubber formulations to improve the processing and curing properties of rubber compounds. It acts as a catalyst in the vulcanization process, speeding up the cross-linking of rubber molecules and enhancing the overall performance of the final product. This results in rubber products that are stronger, more flexible, and better suited for a wide range of applications.

Lithopone B311

ZnSO4 – BaS ➔ BaSO4*ZnS

However, humans are not exposed to E171 in drinking water at any significant quantity over a long duration, so this potential effect is irrelevant to the human experience. It’s important to understand that a potential hazard is not the same thing as an actual risk. 

A significant body of research, mostly from rodent models and in vitro studies, has linked titanium dioxide with health risks related to the gut, including intestinal inflammation, alterations to the gut microbiota, and more. It is classified by the International Agency for Research on Cancer (IARC) in Group 2B, as possibly carcinogenic to humans.

To ensure the optimal precipitation percentage, it is important to carefully control these factors during the precipitation process. For example, a higher concentration of titanium sulfate will typically result in a higher precipitation percentage, but may also lead to the formation of impurities. On the other hand, a lower pH of the reaction mixture can promote the precipitation of titanium hydroxide, but may also result in a lower precipitation percentage.

Nano, or ultrafine, TiO₂ comprises primary particles sized less than 100nm. In this grade, titanium dioxide is transparent (colourless) and boasts improved UV scattering and absorbing properties compared with larger particle-size pigmentary TiO₂.

Over the last several years, nanoparticles have come under scrutiny for adverse health effects. Nanoparticles are ultrafine particles between 1 to 100 nanometers in diameter. (To put this in perspective, the average human hair is around 80,000 nanometers thick.) Because of their size, which can be engineered and manipulated at the atomic or molecular level, nanoparticles exhibit unique physical, chemical, and biological properties. Titanium dioxide is one of the most commonly produced nanoparticles in the world.

New Safety Rulings & Regulations