You need to wear sunscreen when you go to the library, because there are ultraviolet rays when you go to the library. Sunscreen refers to cosmetics with sunscreen that can block or absorb ultraviolet rays and prevent skin from being tanned and sunburned. According to the principle of sunscreen, sunscreen can be divided into physical sunscreen and chemical sunscreen.

Sun protection needs to choose products with different SPF or PA values according to specific objects to achieve the purpose of sun protection.

Introduction to sun protection

Sun protection can be divided into physical sun protection and chemical sun protection, but chemical sun protection is better in skin feeling and visual effect, while people with sensitive or extremely dry skin are more suitable for physical sun protection.

Using sunscreen particles, a protective layer is formed on the skin surface to reflect light waves that may harm the skin in ultraviolet rays, thus achieving the purpose of protecting the skin. Physical sunscreen particles generally stay on the skin surface and will not be absorbed by the skin.

Through the combination of some chemicals and cells, before the cells are damaged, the parts of ultraviolet rays that may harm the skin are absorbed first, so as to achieve the purpose of sun protection.