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Sunscreen is a cosmetic that protects against sunburn and sunburn by adding a sunscreen that blocks or absorbs UV rays. According to the principle of sun protection, sunscreen can be divided into physical sunscreen and chemical sunscreen.
Sunscreens need to choose different SPF or PA values depending on the specific target to achieve the purpose of sun protection. The principle of sunscreen is to isolate the skin from UV rays. Sunscreen lotion and sunscreen, the main difference is the physical properties, the general moisture content of the cream is about 60%, it looks more "thick", it is creamy; and the emulsion, the water content is more than 70%, it looks thin, there are fluidity. Generally, the lotion is more refreshing than the cream because the water content is relatively high, but the formulator can still use different oily ingredients and thickeners to adjust the "greasy" degree of the cream. Therefore, it is still necessary to look at the product itself.