Foams and bubbles are particularly valuable in cosmetics as they can provide functional, sensorial, and emotional benefits. They are ubiquitous in cleaning products for skin and hair containing complex mixtures of short chain surfactants, polymers and other technical (salts, glycols…) or beneficial ingredients (silicones, oils, actives…). Other cosmetic applications (styling, skincare, coloration, etc.) may use foam format for their light feel and easy spreading on hair and skin, covering a wide range of compositions from alcoholic solutions to oily gels.
Besides aspects related to the formation, stability, and structure of foams (that are key in continuously optimizing the performance and usage of foam-based cosmetic products), the right choices of natural and bio-based ingredients will also help to overcome actual challenges such as sustainability. Moreover, their contact and spreading properties on natural surfaces are essential for various applications properties such as cleansing and deposition of topical cosmetic and dermatological products, etc.
In this opinion article, we describe the recent advances and challenges in using foams in cosmetics from both physical and formulation perspectives. We focus our attention on the foam–substrate interaction and recent studies opening new concepts and solutions of interest for cosmetic applications such as foam tribology and deposition.