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J. Cosmet. Sci., 68, 91–98 ( January/February 2017) 91 A general formulation strategy toward long-wear color cosmetics with sebum resistance A podium presentation at the 29th Congress of the IFSCC, Orlando, FL, 2016 ZHI LI, BARTLEY MAXON, KIMMAI NGUYEN, MYOUNGBAE LEE, MENG GU, and PAUL PRETZER, Dow Corning Corporate, Midland, MI. Abstract We propose a “Soft” + “Hard” formulation strategy for long-wear and sebum/oil-resistant makeup. The ratios of “Hard” nonvolatile components (e.g., resins, particulates, and solid emulsifi ers) and compatible “Soft” nonvolatile components (e.g., nonvolatile oils and liquid emulsifi ers) may be carefully adjusted to create desired long-wear performance and sensory. For a given formulation chassis, we recommend studying compatibility and viscoelastic profi les of blends made of “Hard” polymeric resins and “Soft” structuring polymers to gain fundamental understanding of the polymer matrix for pigment adhesion. Enhanced oil/ sebum resistance may be achieved, where there is good compatibility among the “Soft” and “Hard” polymeric components and where there is considerable immiscibility between oil/sebum and each nonvolatile component. Our strategy may help promote cosmetic formulation development based on rational design and understanding interactions among components, develop novel long-wear formulation chassis, and properly evaluate emerging new technologies. INTRODUCTION Since the early 1990s, the product category of long-lasting facial makeup has grown from just for a few niche lines to cover mainstream mass-market offerings and many premier brands. With the selfi e craze, high-defi nition cameras, and multimedia displays, consum- ers nowadays want to look fl awless on social media and in person throughout the day. As a result, our industry has been investing a considerable amount of resources for technical breakthroughs at this frontier (1,2). Recent formulation advances have transformed the perception of these products from drying/tacky and paint-like sensory and appearance to that of regular makeup (1–3). Sebum is recognized as a major cause for makeup deterioration over time. Secreted from human sebaceous glands, sebum is mainly made of triglyceride oils, fatty acids, wax, and squalene. Sebum may not only lead to uneven facial makeup application, but also excessive plasticization of cosmetic fi lms, wetting of pigments, and weakened makeup adhesion to the skin. This can result in oily appearance, makeup shade change, and easier transfer. Address all correspondence to Zhi Li at lizhi99@gmail.com.