​What's the difference between sunscreen spray and sunblock?

Sunscreen spray and sunscreen are mainly the difference in the dosage form, the composition difference is not large, in order to ensure the smooth use of products, many sunscreen sprays have added ethanol as a solvent, as well as gas propellant. From the point of view of the number of sunscreen used in a single product, it is generally about 3-6 kinds, through the combination of a variety of sunscreen agents, and finally obtain satisfactory sunscreen effect.

Sunscreen in sunscreen spray can be divided into two main categories: physical sunscreen and chemical sunscreen.

The sunscreen mechanism of physical sunscreen agent is mainly through the formation of a covering layer on the skin surface, which reflects or scatters the ultraviolet light on the skin surface to reduce the damage of ultraviolet light to the skin and achieve the sunscreen effect. At present, there are only two kinds of physical sunscreen approved for use in China: titanium dioxide and zinc oxide.

Both titanium dioxide and zinc oxide are resistant to UVB and UVA ultraviolet rays, the former mainly targeting the UVB band and the latter mainly targeting the UVA band.

The sun protection mechanism of chemical sunscreen is that the light energy absorbed by ultraviolet rays is converted into heat energy, and the ultraviolet energy is weakened by electronic transition. Some chemical sunscreens may be irritating to the human body, and a few people will have allergic reactions after use, for example, p-aminobenzoic acid and its esters are a common photosensitizer. In addition, oil-soluble sunscreens with smaller molecular weights are like skin penetration enhancers, which are easily absorbed by the skin and even enter the skin stratum corneum, which also has certain safety risks.

Under the same dose of ultraviolet light, the black box is the skin condition without sunscreen products, and the red box is the skin condition after sunscreen products. From the comparison, it can be seen that sunscreen products have obvious protective effects.

If you are intolerant to alcohol, do not use sunscreen sprays containing Physical sunscreen usually stays on the surface of the skin without chemical reaction, relatively safe and mild;Before use, you can do a skin test to determine whether there is irritation, choose mild, non-irritating, suitable for your skin; When using sunscreen spray, mainly spray on the body, it is best not to use the spray on the face, easy to spray into the eyes, and keep at least 15 to 20 centimeters away from the skin;

It is recommended to spray a small amount of multiple times, pay attention to ventilation when spraying, close the mouth and nose, to avoid large inhalation of spray; Sunscreen spray usually contains flammable substances, when used, pay attention to stay away from the fire, to avoid high temperature, impact.