294 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS ELUTION TIME Figure 3. Zirconium polymer distributions for standard (AZG-370) and enhanced efficacy (AZG-375) actives. quite different from preparing AZG materials with large amounts of A1 Kdo.4, but with no concern about Zr chemistry. A practical consequence of the above has been the development of a novel enhanced efficacy tetra AZG powder that contains little A1 Kdo.4, but with careful control of the Zr polymer distribution. Figure 3 shows the Zr polymer distribution of this material (AZG-375) versus that for a standard tetra AZG active (AZG-370) prepared by con- ventional techniques. The lower-molecular-weight Zr polymer distribution for AZG- 375 is the key factor in providing enhanced efficacy. REFERENCES (1) Fitzgerald, Phipps et al., UK Patent Application 2,048,229A (1980). (2) Gosling et al., US Patent 4,359,456 (1982). (3) Markarian and Rosenberg, US Patent 4,818,512 (1989). (4) Callaghan and Phipps, US Patent 4,775,528 (1988). (5) Giovanniello and Howe, US Patent 4,871,515 (1989). (6) Callaghan and Phipps, US Patent 5,298,640 (1994). (7) Rosenberg et al., European Patent Application 0 653 203 A1 (1995). Applications of polyglycerin fatty acid esters to skin care cosmetics JUNICHI NAKAMURA, KAZUHIKO TAKAHASHI, and MASATO TAGAWA, Nikko Chemicals Co., Ltd., Cosmos R&D, Itabashi-ku, Tokyo 174, Japan. INTRODUCTION We have developed polyglycerin fatty acid esters with different functions for skin care

PREPRINTS OF THE 1996 ANNUAL SCIENTIFIC MEETING 295 Table I Formulations of Sunscreen Creams Formulation Cream A Cream B Nikkomulese 41 2.5 % Glyceryl stearate 1.0% Ceteth-20 0.5 Sorbeth-40 tetraoleate 1.0 Behenyl alcohol 5.0 Glyceryl trioctanoate 7.0 7.0 Octyl paramethoxycinnamate 6.0 6.0 Oxybenzone 2.0 2.0 Propylparaben 0.1 0.1 Methylparaben 0.2 0.2 Xanthangum 0.3 0.3 Purified water 81.9 76.9 cosmetics. We found that Nikkomulese 41 (polyglyceryl-10 pentastearate/behenyl al- cohol/sodium stearoyl lactylate) formed a gel network structure in water and that the gel network structure stabilized O/W emulsions. The emulsions prepared with Nikko- mulese 41 had higher water resistance, moisturizing effect, and emulsion stability than those prepared with traditional emulsifiers (ethoxylates). We also developed a new formulation of sunscreen cream containing 8% of micronized pigments by using Nik- komulese 41 to create a gel network structure and by using polyglyceryl-6 ricinolate as a dispersing agent and polyglyceryl-10 isostearate as a co-emulsifier. WATER RESISTANCE (SPF TESTING) The O/W cream prepared with Nikkomulese 41 showed 26% and 91% higher SPF value than a cream prepared with a traditional emulsifier system, under both static and water Figure 1. SPF valt•es of sunscreen creams.