Ever since Ervin Blank discovered1 the importance of moisturizing the stratum corneum, companies have focused their attention on developing a better surface barrier or improving skin surface moisturization in the outer layers of the stratum corneum.
More recently, agents such as peroxisomal proliferator-activated receptor (PPAR) ligands, have been developed and exploited in moisturizers. These agents assist the cellular differentiation process or act as precursors to vital stratum corneum components. Naturally, the benefits from this latter technology can be delivered directly in terms of barrier functionality. However, the newly synthesized stratum corneum needs to be exposed at the outer layers of the stratum corneum to accrue all of the differentiation benefits. This short paper will review some of the research conducted on moisturization technologies over the past decade and give an opinion on future directions.