Recent scientific and regulatory status of color additives subject to the certification in U.S.A. is reviewed in this paper according to various information on the analysis of animal test results, its risk assessment, additional test, regulation U.S. courts of appeals, etc.
The color Task Force Committee of JCIA (Japan Cosmetic Industry Association) examined the safety of provisionally listed color additives which indicated toxicological problems.
And they have submitted to Japanese Authorities the report that contained histories, used volume, progress and evaluation of animal test, importance and needs, and European consideration on D & C Red Nos. 9, 19, and D & C Orange No. 17.
The Authorities consider that it is not urgent to regulate them, and the conclusion is being suspended.
In this paper, the risk assessment of D & C Orange No. 17 is shown with the Japanese points of views together with U.S.A.'s. Higher judgement and more information are expected before the decision and more disputes will be much to come by the Delaney Clause.

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Media with various combination of pH and parabens were inoculated with Asp. niger and Asp. spp. (laboratory isolated) and incubated for 72 hours at 25°C. The relationship of specific growth rates to the pH of medium was investigated by polynomial regression analysis. The quadratic equation expressed the relationship between specific growth rates and the pH of medium. Antimicrobial activity of parabens depended on the concentration of undissociated form in the medium. This study led to the conclusion that estimates of specific growth rates of fungi are obtained through the use of the pH and the concentration of parabens of medium.

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A new simple method for determining sebum excretion is developed. An apparatus named “tip”, which surface is coated with a thin layer of white pigment on a black pigment layer, quickly gives black pattern of sebum by press it to the skin surface. And the blackness of the pattern is proved to be proportional to the amount of skin surface lipid. Thus, this method makes it possible, for anyone to measure sebum amount simply and rapidly. It may be useful as a reasonable indicator for the care of skin healthy and the selection of suitable cosmetics.

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The specific optical phenomenon has been studied in the following system; water-surfactants (nonionic surfactant: anionic surfactant=95:5-99.5:0.5, water: surfactants=80:20)
In order to understand the specific characteristic, polarizing microscopic patterns, viscosity, specific gravity, refractive index, scanning electron microscpic observation and spectram characteristic were mesured.
These are important for the cosmetic chemists who understand for the multilamellar vesicle formation of lyotropic liquid crystal.

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The scientific substantiation of skin treatment efficacy is one of the most important recent tasks for cosmetic scientists. Skin treatment is generally expected to produce psychological effects in addition to dermal physiological and physical effects.
The purpose of this study was to quantitatively measure one aspect of psychological effects, mental relaxation, for substantiating the effects of skin treatment.
For this purpose, we tried to apply some methods of Bio-feedback for Self-control used in Psychosomatic Medicine. From preliminary experiments we chose galvanic skin resistance (G. S. R.) method as the primary measuring method because of its high sensitivity and good reprodubibility. The principle of this method, which is widely recognized in medical field, is based on measuring the variation of G. S. R. of fsngertips, caused by mental perspiration. In our work, G. S. R. was measured with a commercial instrument, but the sensors attached to the skin, the voltage controller and the recorder were modified for higher sensitivity. The G. S. R. sensors were attached to forefinger and middle finger of right hand, and sensors of dermal blood flow (D. B. F.) and pulse wave (P. W.) to fingers of left hand of subject. In order to detect only the effect of skin treatment, measurements were made while the subject was sitting on a chair under normal lighting in a constant temperature and humidity room, without background music.
To study the mental relaxation effects of the skin treatment, we measured the variation of G. S. R., D. B. F., and P. W. in fingertips of about 30 women while their faces were being massaged with varying degrees of pressure with and without using a cold cream. The degrees of massaging pressure were previously determined by an original method, and standardized into 3 grades corresponding to weak, normal and stronge pressure. After massaging for 3 minuits, each subject was inquired to determine the state of mental relaxation using a 4 step evaluation.
G. S. R. of the fingertips of subject whose face was being massaged with a use of a cold cream gradually increased. Statistically, the largest difference in the G. S. R. value was observed before and after the treatment using a cold cream and normal massaging pressure. This difference of G. S. R. value was greater than treatments with weak or strong pressure, or the treatment without using a cold cream. These results correlated well with self-evaluations of mental relaxation. The results of D. B. F. and P. W. data did not show as clear correlation as G. S. R. data.
By using this technique, we were able to substantiate the mental relaxation efficacy of massage treatment by using a cold cream, and evaluate several massaging techniques. Moreover, the technique enables us to study other psychological effects of different cosmetics.

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To create perfumery from heterogeneous image such as a man, scenery, words and so on is in need of originality and the most difficult method of doing now. The cause for this is not only difficult to visualize the image itself but to be hardly clear how to express the visualized image concept and reflect the expression to the perfume.
Then we pay attention to expression and transmission of the perfume and attempt to study how to evolve from the visualized image concept to the terms which express concrete perfumes.
Specially this time, on conversion from sensory terms to professional terms, we don't rely on customary peculiar technique of perfumers but we challenge technical conversion by using objective data with multiple regression analysis.
By this study, we developed the valuable image evolution system on creating perfumery.

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As an instance of cosmetics studies regarding skin-type of user, we tried to examine the difference of sensory evaluation and preference on nourishing creams between Dry-skin and Oily-skin panels.
With 48 nourishing creams and a panel of 99 women whose skin-types were determined by KOSE Skin-type Diagnosis System, the sensory evaluation was carried out. Data obtained were analyzed by two different statistical methods, cluster analysis and principal component analysis.
Then it was found that nourishing creams were evaluated as more richer-type ones by Oily-skin panels than Dry-skin, further the type of favorite creams was different between Dry-skin and Oily-skin panels.

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