HEV Light Protection and Iron Oxides/Titanium Dioxide

Regarding your questions about HEV light protection and the use of Iron Oxides and Titanium Dioxide:

1. White Iron Oxides EasyMix and Titanium Dioxide 200nm EasyDisperse for HEV Light:

   • Based on the product descriptions, Titanium Dioxide 200nm EasyDisperse is specifically for use in make-up products only and is not intended for sunscreen or UV protection. Its description does not mention HEV light protection.
   • White Iron Oxides EasyMix is described as a dispersion-treated powder for use in powder or make-up recipes. While it contains Titanium Dioxide and Mica, its primary function appears to be as a colorant/pigment dispersion for makeup. Its description does not mention HEV light protection or suitability for sunscreen.
   • Therefore, neither of these specific products is presented as providing HEV light protection in the context of sunscreen.

2. Recommended Titanium Dioxide for HEV in Sunscreen:

   • Physical sunscreen ingredients like Titanium Dioxide and Zinc Oxide are known to provide broad-spectrum protection, including some coverage in the HEV range, especially at larger particle sizes or when formulated correctly. Iron oxides, particularly in tinted sunscreens, are also effective at absorbing HEV light.
   • For sunscreen formulations specifically, you should select a Titanium Dioxide product designated for UV protection. Products in the 'Titanium Dioxide for UV Protection' category are formulated for this purpose. Combining these with iron oxides in a tinted formula can enhance HEV protection.

3. Iron Oxide EasyMix Percentage for 4% Pure Iron Oxide:

   • Iron Oxide EasyMix products are dispersions containing iron oxide pigments along with coating agents (like Methicone) and potentially other ingredients (like Mica). They are not 100% pure iron oxide.
   • To achieve a final formula with 4% pure iron oxide, you would need to use a higher percentage of the Iron Oxide EasyMix product. The exact percentage required depends on the concentration of pure iron oxide within the specific EasyMix product you are using. This concentration is not provided in the product descriptions, so the precise percentage of EasyMix needed cannot be calculated without that information.

4. Beige Iron Oxides EasyMix Proportions and Use for Yellow Undertone / Shade #4:

   • Beige Iron Oxides EasyMix contains both Red Iron Oxides (CI 77491) and Yellow Iron Oxides (CI 77492), as listed in its INCI name. However, the specific ratio of red to yellow pigment within the Beige EasyMix product itself is not provided in the description.
   • For skin with a yellow undertone or to achieve a warmer shade like tone #4 on the website, using Beige Iron Oxides EasyMix alone may not be sufficient. You would likely need to adjust the color by adding Yellow Iron Oxides EasyMix to increase the yellow component and potentially Red Iron Oxides EasyMix and Black Iron Oxides EasyMix in small amounts to adjust depth and tone, similar to the examples provided for shades No.2 and No.3. You will need to experiment with the ratios to find the perfect match for your desired shade and undertone.