What is the primary property of titanium dioxide?

Titanium dioxide is primarily recognized for its property of reflecting UV light. This characteristic makes it highly effective as a sunscreen agent and in various cosmetic formulations. When applied to the skin or incorporated into products, titanium dioxide acts as a physical blocker that helps to deflect and scatter ultraviolet radiation, thereby protecting the skin from potential UV damage.

Its ability to reflect UV light is why it is favored in sun protection products, as it provides a physical barrier against both UVA and UVB rays. Moreover, while titanium dioxide can absorb some UV light to a limited extent, its primary function in skincare and cosmetic applications is based on its reflective properties.

In addition, the pigment aspect of titanium dioxide, while notable, is secondary to its role in UV protection. It is not accurate to categorize it solely as a pigment, as its effectiveness in blocking UV rays is a critical property for safety and skincare efficacy. The other choices either misrepresent its primary function or emphasize aspects that are not its main property.