The sunscreen lotion divides into physics and chemistry. Physical sun protection uses physical principles. The lotion’s atomic particles are like a sheet, When you spreads on the face, it works like a mirror to reflect sunlight for skin protection.
Titanium dioxide and zinc oxide are all the ingredients of physical sunscreen.
A protective film can be formed on the skin. Ultraviolet rays cannot penetrate the skin. Both can provide comprehensive UVB protection. zinc oxide can block UVA especially. The typical physical sunscreen ingredients will appear in white and mushy status. It will turn blue when exposed to water. But such products still have some certain limitations for people with darker and drier skin. They need to use cleansing products to help clear…Etc.
Titanium dioxide can block UTA and some UTB. But it cannot fully protect long wavelength’s UTA. For achieving higher SPF but it will appear white.
Zinc oxide can block all the long wavelength’s UTA and UVB. Because It will appear white and thick when you spread so some company develop smaller zinc oxide molecules. It’s called Z-Cote, when you spread on the skin will appear transparent. It improve the above lack and also have protection for long wavelength’s UTA and UVB.
Physical sun protection is made use of the principle of reflection to block ultraviolet rays. These two ingredients will be dispersed in the oil component. Because of its large molecular so it will not be absorbed by the skin. According to experimental research, it is very stable. After 120minutes’s ultraviolet radiation the ingredients are still stable and will not deteriorate.
Stable and not absorbed by the skin, so physical sunscreen is the best choice for atopic skin and baby skin. But the physical sunscreen’s textures are thick and moisturize so not suitable for oil and combination and acne skin. And also will appear white makeup when you spread. So it need some times for those who are not used to make up to adapt.
