In the circumstances of increasing awareness of protecting the skin from UV rays in these days, the need for the function of cosmetic products with UV protection has become diversified not only for leisure in the mountains or the sea but also for daily life. Besides UV protection efficacy, the feeling of less burden on the skin during use involves such aspects as transparency after application, moisturizing effect and comfortable feeling. This article reviews UV filters and the formulation technology using them which focus on both UV protection efficacy and the use sensation, including moisturizing effect.

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In this study, the structure of composites of various cyclodextrins (CDs) and hair setting polymers were analyzed, and improvement of hairstyling performance by including the polymers with cyclodextrins was clarified. One-dimensional ¹H NMR spectroscopy measurements suggested the interaction of polyvinyl pyrrolidone (PVP) and γ-CD. DOSY (two-dimensional diffusion ordered NMR spectroscopy) and one-dimensional NOESY (nuclear Overhauser effect correlated NMR spectroscopy) measurements were used to estimate the structures of the PVP/ γ-CD composite. The spectroscopic analyses and the molecular mechanics calculations suggested that a pseudorotaxane was formed in the PVP/γ-CD composite system. The influence of various CDs on hairstyling performance of various hair setting polymers was examined. The curl-retention measurements revealed that γ-CD characteristically improved the hair setting durability of pyrrolidone polymers such as PVP. In addition, the influence of γ-CD on the hair stiffness of pyrrolidone polymers was studied. The result indicated that γ-CD scarcely influenced the hair stiffness of pyrrolidone polymers. Consequently, it was found that γ-CD improved the hair setting durability of pyrrolidone polymers without a change in hair softness.

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Humectants, such as polyols (glycerol, etc.) and natural moisturizing factor (NMF) , are usually used in cosmetics. Polymer-humectants are also used to improve the moisture-retaining properties of skin. However, most of the polymer-humectants have polarity as hyaluronic acid ; therefore sometimes there are restrictions on their formulation in cosmetics. In this study, we developed a novel nonionic polymer-humectant, poly (methoxy polyethylene glycol methacrylate) (PMMP-9) , which represents excellent skin moisture-retaining properties. The waterholding capacity and water-transpiration suppressibility of PMMP-9 were comparable to those of hyaluronic acid. Furthermore, peel force measurement using a digital force gauge and sensory evaluation suggested that PMMP-9 had a low stickiness compared with general polymers. Evaluation of the softening effect using a Reviscometer™ also suggested that PMMP-9 had an excellent softening effect compared with general polymers. Since it was difficult to provide high moisture retention, low stickiness and softness with one formulation previously, PMMP-9 will prove to be a useful humectant.

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In the cosmetic industry, various keratin proteins have been applied for the protection from hair damage and the restoration of damaged hair. The water-soluble S-carboxymethylalanyl disulfide keratin ( CMADK) protein including the unsymmetrical disulfide groups was synthesized by reduction treatment of wool fiber with sodium thioglycolate and subsequent oxidation with hydrogen peroxide. In an SDS-PAGE method, major bands of 64 kDa and 48 kDa were commonly observed in the newly derivatized protein. The amount of disulfide groups in the protein was analyzed to be 4.4×10^-4 mol/g of protein. The modification of the hair surface with the soluble CMADK protein by covalent SS bonding was expected through the SH/SS interchange reaction between the unsymmetrical disulfide group in the protein and the free thiol group in the hair. The modulus of rigidity based on torsion stress of the hair treated with CMADK protein was increased, and the increased modulus was maintained during the shampooing performed by using a simulation model.

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Ascorbic acid (AsA) is often formulated in cosmetic products for the purpose of antioxidant, whitening, anti-aging and so on. However, AsA is quite unstable in aqueous solution and result in staining with an odorant property. Upon the use of AsA in high-viscous cosmetic products like emulsion or gel formulas, the destruction of the emulsion system and the reduction of viscosity of the formulas caused by the strong ionic character of AsA are large problems for cosmetic chemists. We have developed two new AsA derivatives that have been modified with glycerol. This study showed the advantages of the new AsA derivatives, called glyceryl ascorbates, which had an integrated efficacy taken from both AsA and glycerol. In this study, we investigated their melanogenesis-inhibitory effect, moisturizing effect, characteristic texture and stability in water solution and emulsion/gel.

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