A Novel Technology in Mild and Moisturizing Cleansing Liquids

Skin cleansers have evolved from merely cleansing to providing mildness and moisturizing benefits as well. Alkyl carboxylate, commonly known as soap, is the prototypical surfactant used in skin-cleansing soap bars; however, the superior mildness of syndet bars over soap bars is well documented in the literature. Harsh surfactants in cleansers can cause damage to skin lipids and proteins, leading to after-wash tightness, dryness, barrier damage, irritation, and even itch. The structure of synthetic surfactants is often tailored to minimize damage to the stratum corneum. A significant breakthrough in cleansing came with the introduction of syndet bars containing sodium cocoyl isethionate as the cleanser and long-chain fatty acids as the moisturizing agents. Current liquid cleansers use a combination of anionic and amphoteric surfactants to reduce protein damage and skin irritation potential of anionic surfactants. These combinations can still cause skin dryness, and this article indicates that this may be due to the interaction of surfactants with skin lipids. The combination of anionic and amphoteric surfactants can result in increased damage to lipids, even though their skin irritation potential is reduced considerably. Skin dryness is addressed in current moisturizing cleanser systems with the use of emollients, such as petrolatum and triglyceride oils. Typically, higher levels of petrolatum are used to increase moisturization by occlusion, with some moisturizers having a petrolatum content as high as 50% to 60% by weight. A novel approach to skin moisturization involves using a combination of lipids, natural oils, and humectants, supplemented with occlusives. In this article, we describe the efficacy of a new moisturizing body wash technology, with sodium cocoyl isethionate as the primary surfactant and fatty acids and triglyceride oils as the emollients.