In skin and hair care, selecting the right surfactant system is key to ensuring effective cleansing without compromising the integrity of the skin or scalp. Today, more than ever, consumers are seeking gentle, sensorial formulations that respect the skin’s natural balance. For this reason, mild surfactants have become essential ingredients thanks to their high skin tolerability and their ability to adapt to a wide range of formats and cosmetic needs.
¿Qué son los tensioactivos y por qué son importantes?
Surfactants are molecules with an amphiphilic structure: one hydrophilic part (affinity for water) and one lipophilic part (affinity for lipids). This duality allows them to act as cleansing agents, foaming agents, solubilizers, and emulsifiers. They are found in gels, shampoos, makeup removers, micellar waters, cleansing creams, and other cosmetic products.
Their main function is to reduce surface tension, facilitating the removal of sebum, dirt, pollutants, and makeup residues. However, not all surfactants are the same. Some may be harsh on the skin, while others are specifically formulated to provide a gentle and effective cleansing experience.
Clasificación según carga iónica y comportamiento funcional
The following table summarizes the main types of surfactants according to their charge, main function, and common examples:
| TYPE | CHARGE | MAIN FUNCTION | COMMON EXAMPLES |
| Anionic | Negative | Powerful cleansing, good foaming | Sodium Lauroyl Sarcosinate, Sodium Cocoyl Glutamate |
| Cationic | Positive | Conditioning, affinity with hair fiber | Cetrimonium Chloride |
| Amphoteric | Variable (pH) | Mildness, dermal compatibility, modulators | Cocamidopropyl Betaine, Disodium Cocoamphodiacetate |
| Non-ionic | Neutral | Low irritability, solubilization, mildness | Polysorbate 20, PEG-40 Hydrogenated Castor Oil, Decyl Glucoside |
Beyond the charge, another essential parameter is the hydrophilic-lipophilic balance (HLB). A high HLB (>10) indicates greater water solubility, ideal for O/W emulsions, while a low HLB (<8) is better suited for W/O emulsions. This classification also explains why certain surfactants work better as emulsifiers and others as cleansers.
It’s also important to consider the synergy between different surfactant types. Many formulations combine a primary surfactant with co-surfactants to modulate foam, viscosity, and reduce irritation potential. This strategy allows the creation of customized formulas adapted to various skin or hair needs.
¿Qué hace que un tensioactivo sea “suave”?
To be considered mild, a surfactant must have a low irritant profile, both dermal and ocular. It should also respect the skin’s barrier function, preventing dehydration or microbiome disruption. Biodegradability and sustainable or plant-based origin are also valued.
For instance, amino acid–derived surfactants like Sodium Cocoyl Glutamate or sugar-derived ones like Decyl Glucoside have shown excellent compatibility with sensitive skin. They are often formulated with amphoteric co-surfactants to optimize foam, viscosity, and sensory experience.
Mildness can also be evaluated through TEWL (transepidermal water loss) studies and in vitro assays on epithelial cells. These methods allow comparison of surfactant systems in terms of skin barrier aggressiveness. Advances in skin modeling and reconstructed skin are improving prediction of real consumer responses.
Tensioactivos suaves ideales para cosmética facial
In facial cleansing, balancing efficacy with skin respect is crucial. Surfactants like Sodium Lauroyl Sarcosinate provide deep cleansing without aggressiveness, while others like Coco Glucoside offer a soft and creamy feel, ideal for gel or mousse-type formulas.
Non-ionic solubilizers such as Polysorbate 20 and PEG-40 Hydrogenated Castor Oil are particularly useful in micellar waters or biphasic makeup removers, where ocular tolerance and sensory mildness are priorities. They are also key for solubilizing essential oils, lipophilic extracts, or fragrances in aqueous solutions, maintaining formula clarity without turbidity.
A good facial cleanser with mild surfactants should not only clean but also preserve hydration, avoid tightness, and be compatible with other actives such as ceramides, hyaluronic acid, or niacinamide. In this context, mild surfactant systems become pillars of a solid daily skincare routine.
Tensioactivos suaves en formulaciones capilares
The scalp, like facial skin, can be sensitive to harsh surfactants. For this reason, shampoos and conditioners prioritize ingredients with mild profiles and high dermal compatibility. Sodium Methyl Cocoyl Taurate, for example, is widely used in sulfate-free shampoos due to its good foaming and excellent mildness.
Amphoterics such as Disodium Cocoamphodiacetate and Cocamidopropyl Betaine act as irritation modulators and foam stabilizers. Meanwhile, cationic ingredients like Cetrimonium Chloride provide conditioning, ease of detangling, and shine.
The use of mild surfactants also allows the incorporation of specific actives in hair products, such as hydrolyzed proteins, botanical extracts, or peptides. These systems respect the hair fiber, especially in dyed, damaged, or sensitized hair.
Sostenibilidad y tendencia en surfactantes
The trend towards eco-friendly products has favored the use of biodegradable surfactants from renewable sources, certified by standards like COSMOS or Ecocert. These ingredients not only respect the environment but also align formulations with current consumer values.
Preferences for sulfate-free, silicone-free, and ‘clean label’ products are redefining cosmetic development priorities. Mildness is not just about tolerance but also about brand positioning and storytelling.
Another rising focus is the product life cycle approach. From surfactant production (fermentation, green chemistry) to wastewater impact, formulators are valuing ingredients with low ecological footprints.
Conclusión
Mild surfactants are fundamental to modern cosmetic formulation. Their ability to cleanse effectively without compromising skin or hair health makes them indispensable tools for formulators seeking performance, safety, and sustainability.
Understanding their classification, behavior, and applications enables the development of products adapted to new market demands in both facial and hair care. They also allow innovation in textures, sensorial profiles, and brand narratives aligned with dermocosmetics, sustainability, and functional cosmetics.
Referencias
Kaur, P. (2025). Role of surfactants in cosmetic industry. International Journal of Science and Research Archive, 14(01), 1599–1604. https://doi.org/10.30574/ijsra.2025.14.1.0136:contentReference[oaicite:0]{index=0}
Luengo, G. S., Aubrun, O., & Restagno, F. (2025). Foams in cosmetics: New trends in detergency, friction, coatings. Current Opinion in Colloid & Interface Science, 77, 101906. https://doi.org/10.1016/j.cocis.2025.101906:contentReference[oaicite:1]{index=1}
Nakama, Y. (2017). Surfactants. In Cosmetic Science and Technology: Theoretical Principles and Applications (Chapter 15). Elsevier. https://doi.org/10.1016/B978-0-12-802005-0.00015-X:contentReference[oaicite:2]{index=2}
Prieto-Blanco, M. C., Fernández-Amado, M., López-Mahía, P., Muniategui-Lorenzo, S., & Prada-Rodríguez, D. (2018). Surfactants in Cosmetics: Regulatory Aspects and Analytical Methods. In Analysis of Cosmetic Products (Chapter 11). Elsevier. https://doi.org/10.1016/B978-0-444-63508-2.00011-4:contentReference[oaicite:3]{index=3}