Drometrizole trisiloxane

Ultraviolet radiation is the invisible energy component to sunlight and consists of three wavelength ranges:

(a) UVA is long-range UV radiation between 320-400nm. Although not as energetic as UVB, UVA can penetrate deep into the dermis. UVA can cause immediate tanning, premature skin aging, and can also play a role in the formation of some skin cancers. Approximately 95% of UVA from the sun passes through Earth's ozone layer.

(b) UVB is short-wavelength UV radiation between 280-320nm. It is capable of penetrating the outer protective layer of the skin and is responsible for delayed tanning, sunburns, and most skin cancers. A large amount of UVB is absorbed by the ozone layer, however, as only 5% reaches the Earth's surface.

(c) UVC is comprised of wavelengths between 100-280nm and is very energetic. It is very dangerous to all forms of life, even when the exposure is short. However, UVC radiation is generally filtered out by the ozone layer and never reaches the Earth.

Ultimately, the shorter the wavelength, the more harmful the UV radiation - although shorter wavelength UV radiation is less able to penetrate the skin.

Subsequently, drometrizole trisiloxane is a broad spectrum lipophilic benzotriazole derivative chemical sunscreen that is capable of absorbing UVA and UVB radiation. It is also photostable, meaning that it will not degrade in the presence of sunlight, unlike other UV filters like the widely used UVA absorber avobenzone. When combined with the UV blocker ecamsule, it has been shown that the two UV blockers elicit a synergistic effect involving an enhanced protective action for the skin against UVA and UVB radiation. Additionally, drometrizole trisiloxane is usually combined with other active sunscreen agents like titanium dioxide, avobenzone, and others to ensure the combined product covers or protects against as broad a spectrum of UV radiation as possible, considering drometrizole trisiloxane does not absorb against the entire range of UV radiation.

And finally, at the molecular level, it is believed that the general structure of various UV blockers like drometrizole trisiloxane as aromatic molecules conjugated with carbonyl groups is capable of absorbing high energy ultraviolet rays and then consequently releasing that energy as less harmful, lower energy rays.