It works thanks to elements called "micelles".
A micelle is a complex structure composed of gentle non-ionic surfactants (cleansing agents), in the form of an invisible microsphere.
A surfactant has two different poles:
- a hydrophilic one (which means that it is soluble in water)
- a lipophilic one (which captures fat particles, the latter being incompatible with water)
Whenever the surfactant is aggregated, it shapes into what is called a "micelle", a structure that has the form of an invisible microsphere
Water alone cannot cleanse away all the dirt particles that accumulate on the skin every day, especially the fatty ones. That is the reason why most skincare products contain cleansing agents, called surfactants. There is a very large array of surfactants being used in cosmetics, and some of them can turn out to be unsuitable or too aggressive for the skin. During clean-up, they interact with the diverse components of the skin -- and if the product has been poorly chosen, it can damage the subtle skin hydrolipidic film. Too much cleansing, particularly with abrasive products, is often as noxious as no cleansing at all.
Bioderma's micellar water only use one single surfactant, that is non-ionic and soft to the skin -- a glycerol ester -- whose structure is inspired by the lipids already present in the skin. Thus, the skin's natural barrier is delicately cleansed, in a non-aggressive way.