The advance of foundation makeup technology has made remarkable progress these ten years. The study of formulation, utility or makeup effect have been reported not only in Japan but also in IFSCC and many studies have received prizes, I would like to describe the advance of foundation makeup technology by explaining some research which has been reported.

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In the course of our studies on the further application of licorice as a cosmetic ingredient, we studied a new dermatological availability in the licorice extract containing licochalcone-A as a main principle, Polyol Soluble Licorice Extract P-U, prepared from the roots of Glycyrrhiza inflata Batalin. As a result, this extract showed several activities such as inhibitory actions of testosterone 5α-reductase, lipase and phospholipase A₂, as well as androgen receptor antagonist, antimicrobial and SOD-like actions, which relate to skin care, especially the suppression of acne formation and development. On basis of this evidence, a trial of Polyol Soluble Licorice Extract P-U with acne patients was carried out and the efficacy was demonstrated clinically.

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Sensory properties are very important in efficacy tests of cosmetic products. Several devices for the measurement of tactile sensory properties have been developed in recent years, and we have studied skin surface friction and examined the correlation with skin physiological parameters. The purpose of this study was to determine the relationship between skin frictional parameters and sensory evaluation after application of cosmetics. A KES-SE Frictional Analyzer (Kato Tech Co. Ltd., Japan), a commercial device for the measurement of surface frictional characteristics, was used in this study. An arm holder was added to this device for measurement on the human forearm. Frictional coefficient (MIU) and its mean deviation (MMD) were used as parameters of surface friction. The moisture content in the stratum corneum was measured with a Corneometer CM 825. MIU and MMD were measured immediately, and at 1.5, 4, 5.5 and 7h after application of 9 kinds of moisturizing emulsion with different textures, and the sensory evaluation was made by 6 experts and 149 consumers at almost the same time as the frictional measurement. In the comparison of sensory score with frictional properties, MIU showed a high positive correlation coefficient with hydrate, oily and sticky, while inversely with slippery and dry. It was also shown that oily (aburapposa in Japanese) and hydrate (shittori in Japanese) properties of cosmetics could be examined separately using MIU and MMD. In addition, the changing pattern of MIU with time after application of cosmetics to skin was correlated with fit (najimi in Japanese) assessment. This instrumental analysis may be useful to predict the tactile impression of cosmetics on human skin.

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We evaluated axillary malodor extracted from 66 adult men to identify their key compounds so that deodorants can be formulated to be more effective against them. Using sensory evaluation, we classified the malodors into five groups. Using GC/MS and GC/Olfactory analysis, we identified two key compounds: the vinyl ketones 1-octen-3-one (OEO) and cis-1, 5-octadien-3-one (ODO). Both have a very strong metallic odor and a very low odor threshold. Examination of their generation mechanism revealed that the iron and the unsaturated fatty acids in the living body were related. Morus alba was found to repress the generation of these vinyl ketones due to its remarkable anti-oxidization effect.

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It is well known that short-chain fatty acids, amines and steroids generated by microbial metabolism are the principal compounds responsible for body malodor. We newly identified vinyl ketones (1-octen-3-one, cis-1, 5-octadien-3-one) in body odor and found those ketones are also key compounds in axillary malodor. The purpose of this study was to develop a high performance powder, which has quenching efficacy not only for the shortchain fatty acids and amines, but also vinyl ketones. By investigating various powders known to have quenching efficacy, we finally developed a highly porous silica bead containing magnesium oxide. We found that the superior deodorant effect performed by this powder was the result of the multiple effects of both an excellent physical adsorption capability due to its high porosity and a specific adsorption of vinyl ketones to the magnesium in the powder. An antiperspirant formulation containing both the powder and Morus alba extract showed good efficacy as a deodorant.

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As evidenced by the current prevalence of brown hair among Japanese, the number of people using hair coloring is increasing. The reason for this is that it is becoming more socially acceptable to color one's hair to match mood or clothing or to hide gray hair. The number of people using acid dyes is on the rise, due to their convenience of use. However, the number of complaints of skin staining caused by acid dyes is also increasing. Stains on skin caused by acid dyes generally can not be removed easily. There is no established method for removing stains caused by acid dyes completely and easily. Nishizawa and his colleagues reported the development of acid dyes that do not easily adhere to the skin. However, there is still a great need for new dye removal methods. Therefore, we evaluated solvents and activators of removers by assessing skin permeability and elution from the skin, in order to develop a remover that can easily and safely remove acidic stains from skin.

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