sewing machine with automatic cutter

Résumé–Cet article traite de la découverte de lithopone phosphorescent sur des dessins à l'aquarelle, datés entre 1890 et 1905, de l'artiste Américain John La Farge et de l'histoire du lithopone dans l'industrie des pigments à la fin du 19e et au début du 20e siècle. Malgré de nombreuses qualités souhaitables pour une utilisation en tant que blanc dans les aquarelles et les peintures à l'huile, le développement du lithopone comme pigment pour artistes a été compliqué de par sa tendance à noircir lorsqu'il est exposé au soleil. Sa disponibilité et son usage par les artistes demeurent incertains parce que les catalogues des marchands de couleurs n'étaient généralement pas explicites à indiquer si les pigments blancs contenaient du lithopone. De plus, lors d'un examen visuel, le lithopone peut être confondu avec le blanc de plomb et sa phosphorescence de courte durée peut facilement être ignorée par l'observateur non averti. À ce jour, le lithopone phosphorescent a seulement été documenté sur une autre œuvre: une aquarelle de Van Gogh. En plus de l'histoire de la fabrication du lithopone, cet article décrit le mécanisme de sa phosphorescence et son identification à l'aide de la spectroscopie Raman et de la spectrofluorimétrie.

What titanium dioxide is really emblematic of ... is the failure of FDA to look back at these old decisions and ask whether its decisions that were made in this case ... 56 years ago (in the 1966 approval) still hold up, he said.

Food safety experts in the European Union (EU) have recently updated their safety assessment of TiO₂ as a food additive. In Europe, TiO₂ is referred to as E171, in accordance with European labelling requirements for food additives. The EU expert panel took into account toxicity studies of TiO₂ nanoparticles, which to this point had not been considered relevant to the safety assessment of TiO₂ as a food additive.  

Titanium dioxide (TiO₂). Titanium dioxide is the most common white pigment used today. As a pigment, titanium dioxide is unique because it combines both high colouring and high opacifying capacity. This is mainly due to its high refractive index (2.7). Furthermore, titanium dioxide is an excellent UV absorber (it is used in sun protective creams). Some typical properties are: density 3.3-4.25 g/cm³; pH of water suspension 3.5-10.5; particle size 8–300 nm; oil absorption 10–45 g/100 g; specific surface area 7–160 m²/g. Most titanium dioxide is produced from the rutile (TiO₂) or ilmenite (titanate of ferrous iron). Titanium dioxide can be obtained using different processes.

Lithopone An Essential Ingredient in Paint Production

Titanium dioxide particles help light scatter and reflect, Kelly Johnson-Arbor, MD, a medical toxicology physician at the National Capital Poison Center, told Health. Because of that, we often use it as a whitening agent.

Some websites maintain titanium dioxide is inferior to zinc oxide, another mineral sunscreen ingredient whose core characteristics are similar to those of titanium dioxide. The reality is that titanium dioxide is a great broad-spectrum SPF ingredient and is widely used in all manner of sun-protection products. What gets confusing for some consumers is trying to decipher research that ranks sunscreen ingredients by a UV spectrum graph. By most standards, broad-spectrum coverage for sunscreen ingredients is defined as one that surpasses 360 nanometers (abbreviated as “nm” - how the sun’s rays are measured). Titanium dioxide exceeds this range of protection, but depending on whose research you read, it either performs as well as or slightly below zinc oxide.

Rutile Titanium Dioxide (TiO2) is one of the most widely used and versatile materials in various industries, particularly in coatings and plastics. As a leading supplier of MBR9668, a specialized rutile titanium dioxide coating, companies are empowered to enhance the performance and durability of their products significantly. This article explores the unique properties of MBR9668 and its applications across diverse sectors.

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