ABSTRACT
Moisturizers are one of the most important and commonly used product groups for skin care. Active ingredients used as moisturizers have favorable safety and toxicity properties. To test the efficacy of skin moisturizers, sensitive and reliable methods are required. The most widely used non-invasive approach to measure skin moisture content is by measuring its ability to conduct electrical current. The chapter focuses on the formulation of skin care products for moisturization. A moisturizer usually refers to a formulated product containing an emollient and/or humectant that in combination with water in the formulation provides direct hydration of the stratum corneum. The functional and aesthetic properties of the skin are directly related to skin hydration. Although the stratum corneum has relatively low hydration compared to the viable epidermal regions, the presence of water has an important function in giving the skin surface its elasticity and softness.
