The key role of oils in cosmetic formulations is due to the complex
blend of required properties: innocuity, skin feel, low physiological
impact, stability, spreadability, compatibility with cosmetic
ingredients, functional performances, application to many physical
forms, cost, reproducibility. A new category of hydrocarbons,
hydrogenated polydecenes, performs most of these properties at high
levels. Stability characteristics, solubility with common oils,
emulsification possibilities, pigment wetting power, SPF increase and
dispersion properties are described. The low diffusion into the deeper
layers of the skin is a fundamental key to the safety of these
ingredients and the application to sun protection products, while their
molecular structure accounts for the physical behaviour and functional
performances, like moisturization and anti-wrinkle effect. The easiness
of emulsification and the high dispersion power together with silky to
velvety feel, are very useful properties for new formulation trends