Silica (a form of silicon dioxide) exhibits unique properties in UV absorption and infrared light reflection, which make it widely used in many fields, especially in sunscreen products and coatings.

UV absorption properties

Silica has a strong ability to absorb UV rays. Specifically, it has a high absorption rate of UV light within a wavelength of 400nm, which can reach more than 70%. This absorption ability mainly comes from the high specific surface area and porous structure of silica, which enables it to effectively capture and absorb UV rays, thereby reducing the direct exposure and damage of UV rays to materials. In sunscreen products, this property of silica makes it an ideal UV shielding agent that can protect the skin from UV damage.

Infrared light reflection properties

In addition to UV absorption, silica also has excellent infrared light reflection properties. It also has a high reflectivity of red light (a part of infrared light) with a wavelength of more than 800nm, which can reach more than 70%. This reflection ability helps to reduce the thermal effect of infrared light on the material and improve the thermal insulation performance of the material. In coatings, this property of silica enables it to increase the thermal insulation performance of the coating and reduce the temperature of the coating surface, thereby extending the service life of the coating and maintaining the bright color of the coating.

Application areas

Sunscreen products: As an inorganic UV shielding agent, silica has been widely used in sunscreen products. Compared with organic UV absorbers, silica has the advantages of being non-toxic, odorless, stable, and does not chemically react with other components in the formula. Therefore, it has become an ideal sunscreen ingredient that can protect the skin from UV damage.

Coatings: In coatings, silica is not only used as a filler and thickener, but also improves the anti-aging and thermal insulation properties of the coating due to its excellent UV absorption and infrared light reflection properties. This allows the coating to maintain excellent performance and appearance during long-term use and extend its service life.

In summary, silica exhibits unique properties in UV absorption and infrared light reflection, which give it broad application prospects in fields such as sunscreen products and coatings.