Mask moisturizing principle

When we talk about hydrating and moisturizing, sealants are mainly divided into non physiological lipids and physiological lipids. The former (such as Vaseline and mineral oil) can only form a coating on the surface and reduce TEWL (percutaneous water loss rate); The latter (only refers to fatty acids, ceramide and cholesterol) can not only do so, but also because its composition is the same or similar to the intercellular lipid composition of human stratum corneum, it can go deep into the stratum corneum and participate in lipid formation.

We all know the importance of moisturizing, but moisturizing is not just to make the skin drink "water"! Our skin moisture is absorbed and evaporated at any time. In order to moisturize, we actually need to increase absorption and reduce evaporation.

Increase absorption: multi-purpose water absorbent

The water absorbent can absorb water from the deep layer of the skin (dermis) with high water content, and can also combine with a large number of water molecules in moisturizing products, so as to continuously supply water to the stratum corneum cells on the skin surface. They don't produce water. They are the "porters" of water!

Common water absorbents are:

Glycerol, propylene glycol, butanediol, trehalose, allantoin, hyaluronic acid (hyaluronic acid)

Reduce evaporation: sealing agent cannot be less

Many times, we try our best to add water to the skin and only achieve the first point, but we don't know that if we don't "reduce evaporation", everything is just "surface" Kung Fu! Moreover, it will make the already dry skin worse and drier!

Sealers can form a film on the surface of the skin. This film is usually oily and insoluble in water. It can separate the air from the skin and prevent water evaporation.

Common sealing agents are:

Vaseline, mineral oil, sheep oil, avocado oil, olive oil, shea butter, squalane

Icing on the cake: the wonderful use of bionic agent

In addition to the above two categories, one kind of substances that imitate the skin's own components often appear in moisturizing products. They are called biomimetic agents. Biomimetic agents are also recommended because they have better affinity with the skin!

Common biomimetic agents include:

Hyaluronic acid (also water absorbent), ceramide, phospholipid, linoleic acid