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Authors like to thank Sebastián García (LAMARX) for spectra acquisition, Carolina Leimbruguer for her support with TEM images and Yanina Altamirano, Nicolas Jaime and Javier Reparaz for animal care assistance.
Lithopone is produced by coprecipitation of barium sulfate and zinc sulfide. Most commonly coprecipitation is effected by combining equimolar amounts of zinc sulfate and barium sulfide:
Other scientists, however, have called into question the experimental designs of such studies, citing inconsistent results specifically in studies used to test DNA damage.
This article discusses the discovery of phosphorescent lithopone on watercolor drawings by American artist John La Farge dated between 1890 and 1905 and the history of lithopone in the pigment industry in the late 19th and early 20th centuries. Despite having many desirable qualities for use in white watercolor or oil paints, the development of lithopone as an artists’ pigment was hampered by its tendency to darken in sunlight. Its availability to, and adoption by, artists remain unclear, as colormen's trade catalogs were generally not explicit in describing white pigments as containing lithopone. Further, lithopone may be mistaken for lead white during visual examination and its short-lived phosphorescence can be easily missed by the uninformed observer. Phosphorescent lithopone has been documented on only one other work-to-date: a watercolor by Van Gogh. In addition to the history of lithopone's manufacture, the article details the mechanism for its phosphorescence and its identification aided by Raman spectroscopy and spectrofluorimetry.
VB Chemicals large range of engineered Lithopone “Seal family” fully meets the European regulatory standards and is suitable for every application such as:
Production
Application:
1. Due to its rheological and optical properties, Lithopone offers technical and economic advantages wherever organic and inorganic resin systems need to be relatively highly pigmented for specific applications. Lithopone has therefore traditionally been used in putties, mastics, jointing and sealing compounds, primers, undercoats and marking paints. In powder coatings it is possible to replace TiO2 partially, very economically.
2. The low Mohs' hardness of Lithopone leads to low abrasiveness in comparison with TiO2.
3. Lithopone 30 % (= 30% zinc sulfide share) is proven to be of particular use as a TiO2 Substitute in thermoplastic masterbatches. Even at very high pigment loadings it disperses easily. A masterbatch containing 50 % TiO2 and 25 % Lithopone 30 % DS has the same hiding power as one containing 60 %TiO2. Cost savings are strongly related to the price ratio of Lithopone and TiO2 and the price of for example polyethylene or polypropylene.
4. The Lithopone batch has a much higher extrusion rate too. Furthermore the impact strength of many thermoplastics such as PP and ABS can be noticeably improved by using Lithopone as a TiO2 substitute. Generally spoken, Lithopone can be used at loadings up to 80 % by weight without causing polymer breakdown
Lithopone’s historical significance is further accentuated by the advancements and modifications that followed its inception. The 1874 patent by J.B. Orr, for instance, ushered in a new white pigment—Orr’s Zinc White. This innovation was attained by co-precipitating zinc sulfate and barium sulfide, followed by a calcination process. Further refinements marked the subsequent decades, the most notable being the enhancement of lightfastness achieved in the 1920s by introducing small amounts of cobalt salts before calcination.
Lomon, one of the leading titanium dioxide manufacturers in China, produces the R996 grade titanium dioxide with purity levels exceeding 99%. This high purity ensures that the pigment provides excellent hiding power and color retention in paints, making it a popular choice for the paint industry.
In a 2019 study published in the journal Nanotoxicology, researchers recreated the first phase of digestion in mice and fed them titanium dioxide, then examined whether accumulation occurred in the organs. Researchers wrote: “Significant accumulation of titanium was observed in the liver and intestine of E171-fed mice; in the latter a threefold increase in the number of TiO2 particles was also measured. Titanium accumulation in the liver was associated with necroinflammatory foci containing tissue monocytes/macrophages. Three days after the last dose, increased superoxide production and inflammation were observed in the stomach and intestine. Overall, [this] indicates that the risk for human health associated with dietary exposure to E171 needs to be carefully considered.”
Titanium dioxide is an inert earth mineral used as a thickening, opacifying, and sunscreen ingredient in cosmetics. It protects skin from UVA and UVB radiation and is considered non-risky in terms of of skin sensitivity. Because it is gentle, titanium dioxide is a great sunscreen active for sensitive, redness-prone skin. It’s great for use around the eyes, as it is highly unlikely to cause stinging.


According to the EFSA's Expert Panel on Food Additives and Flavorings 2021 opinion regarding titanium dioxide, it could not rule out a concern for genotoxicity from ingestion of the material based on a perceived gap in data on this risk, which serves as the basis for current ban, said a March report on the decision.
Another key aspect of titanium dioxide manufacturing is research and development. With advancements in technology and the constant demand for higher-performing products, manufacturers must invest in research to stay ahead of the competition. This includes developing new formulations, improving production processes, and exploring innovative applications for titanium dioxide.


