Cosmetics have the basic functions of both protecting the skin and satisfying the user psychologically. The packaging of cosmetics must likewise function to provide the charm of luxury goods and maintain the quality of the product. In other words, the packaging must have an element of a high-quality article which is beyond daily life as well as an element that places it squarely among daily necessities. Naturally this balance changes by the positioning of the brand and the purpose of the article; the price not a uniform thing. The author thinks that this balance is found adjustment in terms of the category of cosmetics. This balance becomes important, but it can be reached through a deep understanding of a detailed exposition of underlying factors. Here the author has written down the factors which should maintain the balance, and details dispenser development that started from these basic conceptions and make-up container development that started from "listening".

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Basics of gentle cleansing for skin and hair are reviewed. In general, cleansing is a practice to remove material deposited as a stain from the object to make it clean. Cleanliness is not always the same and depends on the purpose and object. With regard to the skin and hair, gentle cleansing means sufficient removal of deposition while give functionality of skin or hair. In this regard, the effect of a surfactant in view of gentle cleansing should be sufficient enough to refresh the surface while preserving essential molecules on the objects. Key factors for the mild surfactant are discussed along with the cleansing process.

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Damage due to UV rays induces photoaging such as pigmentation, wrinkles and sagging in the skin. In this study, we focused on finding efficient plant extracts to prevent UV-induced damage, and found remarkable activities in Rose Myrtle (Rhodomyrtus tomentosa) extract and its key component, piceatannol. In evaluations using UVB-damaged human keratinocytes, Rose Myrtle extract and piceatannol, which have inhibitory activity on UVB-induced cell death in keratinocytes, suppressed DNA damage via a decrease of cyclobutane pyrimidine dimer levels and regulation of nucleotide excision repair gene expression. In addition, both Rose Myrtle extract and piceatannol showed anti-oxidative and anti-inflammatory activities such as an increase of glutathione synthesis, inhibition of prostaglandin E2 production and inhibition of interleukin-1β secretion. These results suggested that Rose Myrtle extract might be a useful antiaging ingredient for UV protection and piceatannol may be one of the active components of Rose Myrtle extract.

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A new formulation technique for skin care products, an α-gel holding a large amount of water (LW-α-gel) containing pseudo-ceramide, has been developed. LW-α-gel holds a large amount of water between lamellar bilayers and forms a smoothly-extended film on the skin surface after application. Pseudo-ceramide (P-Cer) , fatty alcohol (C16OH) , and monoglycerin derivative (C16GE) were chosen as the α-gel premixture components. When the pseudo-sphingosine (P-Sp) to LW-α-gel premixture (CPP≈1) ratio was greater than 1/25 and neutralized, interplanar spacing of the lamellar structure was dramatically increased and its appearance turned transparent. By using structural analysis, it was confirmed that an almost uniform and highly ordered lamellar structure was maintained in the continuous phase. We observed that the lamellar film formed a layered structure parallel to the skin surface similar to the lamellar structure of intercellular lipids. LW-α-gel can provide extremely high water holding film property when compared to conventional α-gel. Namely, it was proved that specially-designed LW-α-gel can form an intercellular lipid-like lamellar film on skin. LW-α-gel's skin moisturizing efficacy was evaluated. The stratum corneum's continuous water holding property was observed even 6 h after LW-α-gel application. Improvement in transepidermal water loss was observed and P-Cer penetration increased. In the 2-week home use test, significant improvement in dry skin scaling was observed. These results were supported by observations of P-Cer's low melting enthalpy and the lamellar film's water holding property.

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Cholesterol had been used for a long time as the technique for suppressing the leakage of inclusions on liposome. The effect of leakage suppression on inclusions of cholesterol above the phase transition temperature was known. However, there has been a problem that the leakage of the inclusions below the phase transition temperature cannot be fully suppressed. Therefore, we examined various combined lipids to find an ingredient to suppress the leakage of the inclusions on liposome below the phase transition temperature. As a result, we found that 1, 2-alcanediols (carbon chain length C8-10) suppress the leakage from liposome compared with the cholesterol. The effect of 1, 2-decanediol is especially high because 1, 2-decanediol suppresses the fluidity of the hydrophilic and hydrophobic groups of the membrane of liposome below 45°C . From these results, we found that leakage of the inclusions are suppressed in the temperature range below the phase transition temperature by adding 1, 2-decanediol. It wasconfirmed that liposome which consists of the above ingredient possesses a controlled-release effect at skin temperature (33°C).

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Recently, there has been a great demand in the cosmetic industry for development of a new chemical which shows preservative effects. In this study, to meet the industrial demand, 4 kinds of alkyl dimethylol alkanates (ADMA) were synthesized and were evaluated for their antimicrobial activities. In addition, the antimicrobial action mechanisms of ADMA were discussed with their interfacial parameters in water solution. In the results, hexyl dimethylol propionate gave a superior antimicrobial effect among ADMAs. In addition, the surface tension measurement in water solution suggested that the ADMA with higher antimicrobial ability showed a tendency to be absorbed interfacially and to be well-packed on the interface. Antimicrobial parameters of ADMA, which were calculated from the results of antimicrobial tests, demonstrated positive correlations with interfacial parameters, especially cmc/C20 and Γ_cmc. Therefore, it was concluded that the interfacial parameters could be a screening parameter for developing antimicrobial components.

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