Emollient agents are key ingredients in many cosmetic formulations, whether they are moisturising creams, hair care products or makeup items. While most cosmetic enthusiasts are aware of their ability to protect and soften the skin, few know that they possess other interesting properties. Let's explore together the various roles of emollients.
What is an emollient agent?
Published on November 27, 2024, by Pauline, Chemical Engineer — 5 min of reading
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Emollient Agent: What are we talking about?
Emollients are among the most frequently used ingredients in cosmetic formulation. They have been utilised for several centuries, and historical records dating back to around 700 BC inform us that the Ancient Greeks were already using wool fat with the aim of softening their skin. The term 'emollient' actually originates from the Greek word "malakox", which means soft, tender, delicate. In cosmetics, the primary function of emollients is to soften the skin tissues.
Emollients are cosmetic ingredients designed to make the stratum corneum more supple and flexible by increasing its hydration.
The primary function of emollient agents is to promote the accumulation of water in the stratum corneum. This property is highly beneficial as the water content of the stratum corneum controls the biomechanical properties of the skin, that is, its suppleness, elasticity, and firmness. Therefore, it is advantageous to use cosmetics that enhance the cohesion between the lipids in the intercellular space, particularly ceramides, whose main role is to hinder the movement of water through the stratum corneum and thus limit transepidermal water loss. Certain emollient agents can act in this way and insert themselves between the lipids of the stratum corneum, thereby strengthening the barrier function of the epidermis.
Another interesting property of emollients: their ability to create a protective film that strengthens the natural hydrolipidic film present on the skin's surface, also acting to limit water loss and reduce the risk of pathogenic agents or pollution particles penetrating the epidermis. In this respect, emollient agents are quite similar to film-forming agents, although the barrier they form is generally less occlusive than that of film-forming ingredients. Finally, by softening the surface of the skin or hair, emollients reduce sensations of roughness or tightness, making the skin more flexible but also more pleasant to the touch. The main emollient agents used in cosmetics are gathered in the table below.
| Emollient Family | Examples | Properties |
|---|---|---|
| Vegetable Oils and Butters | Argan oil, sunflower oil, coconut oil, shea butter, mango butter... | They provide fatty acids, nourish the skin, and form a moisturising protective film that reduces transepidermal water loss. |
| Silicones | Dimethicone, Cyclopentasiloxane | Create a protective and impermeable barrier, provide a smooth touch and help to reduce transepidermal water loss. |
| Mineral Oils and Waxes | Paraffin, petroleum jelly | Forms an occlusive barrier that retains moisture in the skin. |
| Aloe vera | / | A natural moisturising and emollient agent that enhances the moisture in the stratum corneum. |
| Fatty alcohols | Cetostearyl alcohol, cetyl alcohol, behenyl alcohol | Emollients and thickeners, they soften and make the skin more supple while improving the spread of skincare treatments. |
| Waxes | Beeswax, carnauba wax | They provide consistency and texture to formulations while forming a protective barrier that limits skin dehydration. |
| Lanolin and its derivatives | Lanolin, lanolin alcohol | Form a protective barrier and promote long-lasting hydration. |
| Squalane | / | Naturally present in sebum, squalane strengthens the hydrolipidic film and leaves the skin soft. |
| Glycerol Derivatives | Tricaprylin, tristearin | Primarily used to enhance the texture of products, they also boost the hydration and protection of the skin and hair. |
Les principaux agents émollients utilisés en cosmétique.
Note : The use of emollients extends beyond the cosmetic field and into the medical sphere. Indeed, it is not uncommon to find emollients in ointments or topical medications intended for people suffering from eczema, psoriasis or presenting a wound.
Sources
DRAELOS Z. Cosmetics and skin care products. A historical perspective. Dermatologic Clinics (2000).
LUGOVIC L. & al. The Use of Emollients as Sophisticated Therapy in Dermatology. Acta Dermatovenerologica Croatica (2003).
LODEN M. & al. Role of Topical Emollients and Moisturizers in the Treatment of Dry Skin Barrier Disorders. American Journal of Clinical Dermatology (2012).
BAKI G. Introduction to Cosmetic Formulation and Technology. Wiley (2023).
