Skin that's six degrees cooler. This is the promise of the new refreshing sunscreen developed by a team of researchers. A prototype that combines UV protection and skin cooling, surpassing the performance of any product currently on the market. Will it make it to market by the next, predictable, torrid summer?
Radiative cooling technology
The secret of this refreshing sunscreen lies in the radiative cooling, a technology already successfully used in cooling fabrics and in whitest paint in the worldThe latter is so effective at reflecting light that any surface covered by it maintains a constant temperature. several degrees lower than the ambient temperature.
The prototype exploits the properties of specific substances to reflect light and heat, while simultaneously protecting the skin. Tests have shown that it can keep skin between 4,2 and 6°C cooler than unprotected skin, and up to 6,1°C cooler than traditional sunscreens.
Refreshing sunscreen, the formula is (relatively) simple
The refreshing sunscreen is composed of six key ingredients: in order of availability? Deionized water, ethanol, cream Nivea, kaolin pigments, a silicone polymer called polydimethylsiloxane and titanium dioxide nanoparticles. The latter is already widely used in commercial sunscreens and the nanoparticles are considered safe for the skin.
The secret lies in the Optimized size of titanium dioxide nanoparticles, which allow for simultaneous UV reflection and radiative cooling effect
The formula has been proven to have a sun protection factor (SPF) of 51, thus offering excellent protection from UV rays. It is also water resistant and maintains its effectiveness for 12 hours of exposure to simulated sunlight.
Tests and performances
Researchers subjected the cooling sunscreen to rigorous tests in a hot and humid environment to evaluate its radiative cooling effect. The formulation proved not only effective but also economically sustainable, with an estimated cost of 0,88 euros for 10 grams, in line with the products currently available on the market.
Safety tests have confirmed the absence of skin irritation, a fundamental aspect for any product intended for application on the skin. The long-lasting protective and refreshing effect, together with water resistance, make this innovation particularly promising for everyday use.
Refreshing sunscreen, future prospects
With global temperatures rising due to the climate crisis, the development of an effective cooling sunscreen is not news to ignore. Researchers believe that this technology has high commercialization potential and could be an important tool for protecting people.
The research, published in the journal Nano Letters ofAmerican Chemical Society (I link it to you here), paves the way for a new generation of sun protection products that do not simply shield from UV rays, but actively contribute to the thermal comfort of the skin.
