It is used in cosmetics as a thickening, whitening, lubricating, and sunscreen active ingredient. It protects the skin from UVA and UVB rays and poses no threat of skin sensitivity. Titanium dioxide is an excellent sunscreen active for sensitive, redness-prone skin due to its gentle nature. It is ideal for use around the eyes since it is unlikely to sting.

Titanium dioxide is usually micronized and coated before being used in cosmetics. The micronization makes this very heavy-feeling ingredient more spreadable and more cosmetically appealing. Micronized titanium dioxide is much more stable than the non-micronized version and provides more superior sun protection. Micronized titanium dioxide does not penetrate the skin, there is no need to worry about it entering the bloodstream. The molecular size of nano titanium dioxide is big enough that it does not penetrate beyond the stratum corneum. Titanium dioxide becomes more unobtrusive as particle size decreases. Large particles tend to leave a whitish appearance on the skin. This is particularly evident in photos using flash photography.

While titanium dioxide does not perform as well as zinc oxide in terms of UVA safety, the difference is marginal. Since this is difficult to understand in terms of other factors influencing how sunscreen actives work (such as other active ingredients), many people believe that zinc oxide is superior to titanium dioxide for UVA safety. Titanium dioxide, when carefully formulated, offers excellent UVA protection. Its UVA safety peak is lower than zinc oxide's, but both continue to provide UVA protection for the same period of time.

See also:
Sun Protection Factor
Zinc Oxide
UVA
UVB((n)