This paper was presented at the “U.S.-JAPAN Society of Cosmetic Chemists Joint One Day Symposium” held on October 19, 1978 in Tokyo to describe the Japanese cosmetic industry for the U.S. delegation and to discuss together in regard to many problems we, as cosmetic chemist, have been facing with.
The present status of Japanese cosmetic industry including cosmetic sales, item by item analysis and characteristics of the market etc. is described taking the Japanese tradition, way of thinking and geographical characteristics into cosideration, and a basic concept employed in quality assurance in Japan is also described by indicating actual examples such as tests and procedure needed for quality assurance. As a problem the Japanese cosmetic industry has to face with, the amendment of Japan's Pharmaceutical Affairs Law is taken and studied for the possible impacts of its articles on cosmetics. Since the development of “Safer and more beneficial cosmetics” has become more difficult because of a great concern for safety, a great anticipation is expected of the cosmetic chemists and for this reason, it is emphasizcd that world-wide system of information exchanges and cooperation amongst the cosmetic chemists is really needed to solve the common problems.

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This study concerns with the variation of transepidermal water loss when emollients are applied to the human skin.
Our experimental results; The effect of decreasing transepidermal water loss depends on thickness and properties of remaining film on the skin after applying cosmetic creams. Moreover, this effect correlates with the feeling of the film after applicaion, that is, the degree of “oiliness” by sensory test of creams.
We developed in vitro method which gave good correlation with in vivo method and confirmed these effects.

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For the purpose of investigating the related factors to the practical use of the sunscreen products in Japan, we have investigated about ultraviolet amounts, wavelength and reflectance in some outdoor sports environments, especially in skiing resort and summer beach as a physical factor, and the relationship between the skin complexions and their susceptibility to sunburn and suntan as a biological factor,
For measuring the range of 300-320nm (UV-B) and 300-390nm of ultraviolet radiation, each 2 of 2 types integrating actinometers were equipped with the phototubes consisting of the optical filters and diffusion filters. The reflected or scattered UV-radiation from downwards was measured by setting the detecting surface of the phototube to downward in vertical position.
Sun exposure tests for investigating Japanese suceptibility to sunburn and suntan were done at Okinawa (26°N) and Shizuoka (34°N) in July. Prior to the tests, Japanese skin complexions were classified to 3 groups, the fair, the medium and the dark based on the results of a selfassesment of his own skin, the visual evaluation by 3 examiners and the colorimetric study.
Average UV-B ratio to 300-390nm from January to March was 9.9% on fair days, 7.9% on cloudy and 5.6% on rainy in Yokohama city, while in skiing resort was 8.7% on fair days and 6.4% on snowstormy days.
The reflectace of UV-radiation under some natural environments was measured. Dry sands on beach reflected by 7.5%, while the reflectance was only 3.7% on wet sands. The average value on snow surface reached 88.0%, this is unusually high. Outside snow and sands, lawn reflected by 1.2% and concrete surface by 5.5%.
MED (×0.18mw.min/cm²) was 600 for the fair skin subjects, 800 for the medium skin and 1100 for the dark skin, respectively. However, no difference was observed among the MMD (Minimum Melanogenesis Dose) regardless if the skin complexion of Japanese subjects.
3 patterns of sunburn and sutan were deduced for the people with various skin complexions: 1) Fair-skinned people will not have suntan if they do not suffer sunburn to some extent 2) In the case of dark-skinned people, they will readily be suntanned without sunburn 3) People with medium skin are between the two that is some of them may be suntanned after slight sunburn.
Furtheremore, colorimetric study on sunburn and suntan was made with fair skins and dark skins after single sun exposure.

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The occlusivity of oils was determined in vivo by measuring the suppression of transepidermal water loss (TEWL) of the skin. Various emollients were applied to human skin in various forms including powders, solutions, and emulsions of different types having different size distributions and the residual states of the oil films on the skin surface were examined with time. In order to discuss the occlusivity in relation with the individual skin conditions, the surface temperature of the skin and the casual lipid level were also determined in each subject. The followings are the results obtained from these experiments.
1. The occlusivity of the oil films varied with time, nature of the oil, amount of the oil, physical forms of the oil, type of the emulsion, and droplet diameter of the emulsion.
2. The occlusion effect of the oil also depended upon the characteristics of the skin such as casual lipid level and TEWL.
These results could be explained by the differences in such as uniformity, spreadability, and porosity of the oil films on the skin surface in the residual state. It is believed that the emolliency of the oil can be influenced by these differences.

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An objective system is described which enables measurement of the skin roughness of a selected small area by means of a surface tracing and a computer analyzing techniques. The system consists of five basic steps; 1) replicating the area of skin surface on a small celluloid plate, 2) tracing on the replica plate using an instrument, SURFCOM, 3) simultaneously, recording the roughness information by a cassette data recorder, 4) analyzing the analog data of roughness by a computer, 5) finally, representing the results as a “Stereograph” by a digital plotter and computing the data to obtain a “Roughness Profile”.
The Stereograph and Roughness Profile of those replica clearly demonstrated that the difference between a typically rough skin and a smooth skin can be measured adequately and quantitatively by the proposed system.
Furthermore, the system in also quite valuable in measuring the effect of skin treatment such as massaging and mask treatment.
The results confirm our observation through the micrography that a massage and a mask treatment using cosmetic preparations flatten the structure of skin surface. Moreover they give us new quantitative informations about cosmetic efficacy substantiation.

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The photoprotective aspect of urocanic acid as a natural sunscreen agent in the human skin surface was studied. At first, a new method for the fractional determination of trace amount of geometrical isomers of urocanic acid was developed by high performance liquid chromatography. The limit of detection was 2.4ng for cis urocanic acid and 2.0ng for trans urocanic acid, respectively. Then, influence of age, sex, sampling position of human materials and seasons upon the total amount of urocanic acid and the ratio of geometrical isomers (cis and trans isomer) in the human skin surface were determined in detail using this analytical method. Moreover, the photoisomerization of urocanic acid in water was observed and the protection factors of sodium trans urocanic acid and photoisomerized sodium urocanic acid were experimentally compared. The obtained results showed that both isomers acted as sunscreen agents and suggested that photoprotective effect arose from not only isomerization energy but also photo absorption.

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1, 500 profile data for 30 well-known perfumes on the market analized, and the following results were obtained.
1) Odor imprssion of perfumes can be expressed by three factors, “Heaviness”, “Worthiness”, and “Uniqueness”.
2) There are clear relationships between the odor impressions and the odor types, and the similar type of odor make a group in the odor-describing space.
A computer program was developed to punch out three factor scores and five “Proximate Perfumes” When the profile data was entered (proximate perfumes refer to the ones which give impressions similar to the sample odor).
Several sets of data, including the imaginative odor, were entered to the computer in order to test the practical application of this systems.

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