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Le lithopone a été découvert dans les années 1870 par DuPont. Il a été produit par la Krebs Pigments and Chemical Company, entre autres¹. Il se faisait en différents grades, en fonction de la teneur en sulfure de zinc. Les qualités « bronze » et « or » contenaient 40 à 50 % de sulfure de zinc, ce qui les rendaient particulièrement couvrantes². Bien que ce pigment ait atteint son pic de popularité autour de 1920, il s'en produisait encore annuellement plus de 220 000 tonnes en 1990. Il est principalement utilisé dans les peintures, les pâtes et les plastiques³.

Titanium dioxide (TiO₂) is a multifunctional semiconductor that exists in three crystalline forms: anatase, rutile, and brookite. Owing to an appropriate combination of physical and chemical properties, environmental compatibility, and low production cost, polycrystalline TiO₂ has found a large variety of applications and is considered to be a promising material for future technologies. One of the most distinctive physical properties of this material is its high photocatalytic activity (Nam et al., 2019); however, more recently it has attracted growing interest because of its resistive switching abilities (Yang et al., 2008).

Moreover, the region of sourcing can also impact pricing. Suppliers in different geographical locations may offer varied prices due to differences in transportation costs, availability of raw materials, and local market conditions. Buyers must consider these regional variances when negotiating prices and establishing long-term relationships with suppliers. In many cases, sourcing from manufacturers that can produce high-quality lithopone pigments at competitive rates can lead to significant cost savings.

Australian researchers examined how titanium dioxide as a food additive affected gut microbiota in mice by orally administering it in drinking water. The study, published in the journal Frontiers in Nutrition in 2019, found the treatment could “alter the release of bacterial metabolites in vivo and affect the spatial distribution of commensal bacteria in vitro by promoting biofilm formation. We also found reduced expression of the colonic mucin 2 gene, a key component of the intestinal mucus layer, and increased expression of the beta defensin gene, indicating that titanium dioxide significantly impacts gut homeostasis.” The changes were then linked to colonic inflammation, along with a higher expression of inflammatory cytokines, which are signal proteins that help with regulation. The researchers concluded that titanium dioxide “impairs gut homeostasis which may in turn prime the host for disease development.”

Challenges and Innovations

The brands of lithopone of the normal class, that of chemical manufacture, are marketed under such names as Ponolith, Beckton White, Jersey Lily White, Oleum White, Zinc Sulphide White, all of these being of domestic manufacture, and their composition is of the 30 per cent. zinc sulphide type. The German manufacturers and exporters of lithopone make use of fancy names for their brands and here are a few examples of these and the composition of the pigment:-

There are numerous manufacturers of titanium dioxide; the largest include Delaware-based Chemours (a spin-off of DuPont Chemical), Texas-based Kronos, and China-based Lomon Billions Group, all of which manufacture pigments for use in products like paints, coatings, and plastics. UK-based Venator is a major supplier of titanium dioxide used in food and cosmetics, along with paints, paper, plastic, and more. As a pigment, it is called Pigment White 6 (PW6), titanium white, or CI 77891. As a food additive, it is known as E171.