What does sun protection mainly anti?

We all know that beauty to the sun, but also know mainly to prevent the sun's UV rays, but they do not know what kind of sunscreen to give skin protection. In fact, mainly to prevent sunburn sunscreen to prevent skin melanin, as well as to prevent skin photoaging and prevent stain formation. hdfuih68
The solar ultraviolet UVA and UVB are the two great harm to the skin of ultraviolet rays, but also a major sunscreen to prevent objects. UVA UVA is, is that it gives the skin photoaging,Cleansing System  premature aging. And UVA can penetrate the dermis, the skin tan, and cause damage to lipids and collagen, so skin photoaging and even skin cancer.

UVB what is it? It is another kind of solar ultraviolet UVB, it can reach the dermis, the skin can cause skin peeling sunburn, erythema and tanning phenomenon. UVB damage to the skin is relatively small and can easily be obscured glass and umbrellas, or clothes, but it is also the main target of the sun.
Sun's UV rays is mainly these two wavelengths, another short-wave UV UVC, but this one wavelength is difficult to penetrate the atmosphere, usually in the ozone layer will isolate out. So Sun is mainly to prevent the above two kinds of solar ultraviolet wavelengths.