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J. Cosmet. Sci., 69, 131–143 (March/April 2018) 131 Reducing Facial Wrinkle Size and Increasing Skin Firmness Using Skin Care Polymers MARC N.G. DE MUL, TANYA UDDIN, XI YAN, AMBER HUBSCHMITT, BJÖRN KLOTZ, and WENDY KIN MAN CHAN, BASF Corporation, Tarrytown, New York, NY 10591 (M.N.G.d.M., T.U., X.Y., A.H., W.K.M.C.) and BASF Personal Care and Nutrition GmbH, Düsseldorf 40589, Germany (B.K.) Accepted for publication January 28, 2018. Synopsis Many cosmetic polymers shrink on drying, producing a tensile force if coated on a substrate. This tensile force can be used to smoothen wrinkles and pores in facial skin. In this study, we evaluated two polymers, a polyvinylpyrrolidone (PVP) and a polyacrylate, for skin tightening properties. We conducted a double-blinded, placebo-controlled and randomized clinical study with 32 female volunteers aged 35–65 years who perceived themselves to have a loss of skin elasticity. Both polymers were formulated in a model cosmetic emulsion with hydrogenated polyisobutene as the oil phase. We measured skin fi rmness and tightening parameters at baseline and after each product application. Also, facial images were recorded with a fringe projection instrument. The fi rming measurements indicated that both polymers instantly tightened facial skin, whereas the placebo product offered no signifi cant tightening benefi t. However, in clinical evaluation, only the polyacrylate polymer produced statistically signifi cant improvements in wrinkle size and skin fi rmness on the face without signifi cant consumer use complaints such as tackiness. We concluded that skin care products using PVP and polyacrylates have the potential to offer immediate and visible benefi ts to consumers with aged skin. INTRODUCTION Erasing the effects of age on the face is one of the most elusive benefi ts that consumers seek in skin care products. Myriad products are available in commerce today that claim to make consumers appear younger. However, most work by fi lling in and covering up wrinkles, age spots, and other attributes of aged skin, and others have effects on aged skin that are measured as relatively small improvements over prolonged treatment periods. All must be applied daily for a sustained effect, in contrast to surgical treatments that have a long-term benefi t. Antiaging skin care products generally contain emollient oils and emulsifi ers in an aqueous base. Such products moisturize the skin and may improve the tactile properties perceived Address all correspondence to Marc N.G. de Mul at marc.demul@basf.com. This work was funded by BASF Corporation.