Published online by Cambridge University Press: 31 January 2011
Cosmetics are products that are designed to maintain or improve visual appearance when applied to skin. Skin is a mechanically flexible substrate that changes in chemical and surface properties during the course of the day. Sebum (an oily substance secreted by the sebaceous glands) and perspiration (a secretion of mostly salt water by the eccrine glands) as well as environmental insults work counter to the desired benefits of cosmetics on physical appearance. Recent advances in the ability to control morphology and chemical properties have led to novel materials that in turn have enabled the development of cosmetics that provide, on the one hand, a more natural look, and on the other, unique and unprecedented visual effects. Progress in understanding skin biomechanics and surface properties lead to product formulations with unprecedented wear and performance characteristics. This article reviews recent advances in the ability to control the optical, bulk, and surface properties of materials, and their application to improved cosmetic formulations.