Слънцезащита 2018

Iron Oxides

We most commonly see iron oxide in two areas; as rust on exposed iron and in cosmetics, where it is employed to give the cover-up color desired. While not approved by the FDA as an active ingredient in sunscreens, many companies use iron oxides in their sunscreen products. Cosmetic iron oxides are man-made to very high levels of purity, desired color and particle size.

Iron oxide pigments for cosmetic use are micronized powders. By controlling the purity, particle size, temperature, and rate of drying during manufacture, they have become available in a number of shades and tones of red, yellow, black, and brown (and blends of these basic colors). These cosmetic pigments, if incorporated at adequate concentrations and when properly dispersed in well-designed vehicles, not only add color to the lotion (or cream, powder, etc.), but contribute significantly to protecting the skin from many wavelengths of light.

Ultra-submicronized iron oxides protect against visible light waves, yet add little color to the finished product. This allows for the addition of higher levels of infrared protecting iron oxide while retaining the cosmetic elegance and shade of the final preparation. Considerable blocking of ultraviolet rays is also reported with submicronized iron oxides, complementing further the primary UV blocking agents.

Indirect Physical Blocker Aids

Examples of these particles can be natural talc or mica. They are usually flat and oval in shape. They are very small particles, though they are much larger than direct physical blockers. A portion of very small physical blocker particles will coat the larger flat talc (mica, etc.). Being flat and smooth, the coated particles of talc easily slide over each other, overlapping themselves and effectively increasing protective coverage on the skin.