Control of the Physical Properties of Wax Gels and Their Application to Cosmetics

Abstract

Wax gels consisting of oils and waxes (e.g., paraffin or botanical waxes) are used in various cosmetics such as lipstick, lip cream, eyeshadow, and foundation. Since the wax gel has a frame work, called the card-house structure, formed by combining crystallites, the physical properties of the gels or the relationship between the gel hardness and the polarity of oils used is different from those of ordinary organogels. Furthermore, mixing waxes with different molecular structures can drastically alter the hardness of the gel and the retention of oil. In this technical review, the relationship between the microstructure of wax gels and the oil solidification ability is clarified. We also describe the techniques to control the physical properties of wax gels suitable for cosmetic products.