There is great variation in the nature and quality of facial skin in women. In the cosmetics industry, these variations in skin type have been classified subjectively as either oily, normal, or dry. Several physiological parameters of the skin were measured in an attempt to develop a scientific method for classifying skin types. Eighty women (age 20 to 59) participated in this one year study. Each was administered a skin type self-estimation questionnaire six times and answered puestions about the nature of their own skin. Parameters such as skin surface lipid quantity, transepideramal water loss (TWL), skin surface morphology, conversion rate of glutamic acid to pyrrolidone carboxylic acid (PCA%) were measured at the same time the self-estimation questionnaires ware given.
It was found that skin type is classified subjectively based on the independent sensations of “dryness” and “oiliness”. The former corresponded to TWL, skin surface morphology, and PCA% and the latter to skin surface lipid. The conventional skin classification procedure depends mainly on the level of skin surface lipids. This paper confirmed the existence of other parameters related to dryness.
Previous studies by the authors revealed that surface morphology reflected the biochemical events of keratinization, such as free amino acid metabolism including the glutamic acid to pyrrolidone carboxylic acid conversion rate, and also had a close relationship with TWL showing water barrier function and skin surface conductance indicating the water content of the stratum corneum. Thus, these parameters were found to be a valuable index for the water holding capacity of the skin.
A scientific method of skin classification based on the two factors of water holding capacity and skin surface lipid was developed. In addition to the three generally recognized skin types, an oily skin type characterized by dryness and roughness was identified. This paper presents a simple and reliable method for classifying skin types which has been approved from both dermatological and cosmetological aspects.

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In order to obtain a excellent-quality foundation, it is important that the shade of the foundation applied to the skin corresponds well to the cake color. However, the shade of applied foundation tends to shift toward a more reddish tone than the cake color. Also the color-shift toward reddish tone is generally observed during the pigment dispersion process. We investigated the causes of these color changes from a view point of color extension properties of RED, YELLOW and BLACK iron oxides.
Powders and oils were mixed in a laboratory grinding machine after mixing with a household mixer, and the mixture was taken at intervals and pressed. Evaluation of the shades of applied foundation samples was performed by applying the powders to white porous polyvinylalcohol sheets. Samples were applied to the sheets by using dry applicator with weak, medium or strong shear. Color measurement was made by using a spectrophotometric colorimeter.
Application tests and microscopic examinations suggest that further color extension occurs during application of foundation, and this color extension results in the discrepancy between the cake color and the color of applied powder. A new measure for the evaluation of the degree of color extension was devised. This measure was confirmed to correspond well to human visual sensation, and was found to be useful for comparing the rates of color extension of pigments. The rate of color extension varied in the order: YELLOW<acicular RED<granular RED<BLACK at respective pigment concentrations similar to those in foundations. This result explains color darkening and changing toward reddish tones during the pigment dispersion process or during application, because YELLOW extends fully in early stage of the process but RED, especially in granular form, and BLACK continue to extend even in the late stage or during application. Acicular iron oxides extend more rapidly, because their aggregate structure is bulkier and looser than that of granular ones.
Acicular RED iron oxide is therefore more favorably employed to attain sufficient color extension of foundation with lower energy expenditure, and to minimize the discrepancy between cake color and the color of applied powder.

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The purpose of this study was to enable to characterize the facial color change due to aging, and to substantiate the effectiveness of color control by makeups.
We measured skin color of 5 facial areas of 300 Japanese women between 16 to 68 years old, during April. The aging effects of facial color were characterized by the color distribution in different facial areas. It was found that the distribution came narrower with aging, and the facial color became more uniform and darker. The most natable color change due to aging occured in cheek area of women between twenties and thirties, and the least color change was observed in neck area.
To study the coloring effect of base makeup, we also measured the skin colors of 25 Women before and after applying several different cosmetics, and found that the color of skin after the application could be predicted from a proper function of bare skin color by a regression analysis.
By combining the information from the study on the apparent change in color distribution due to aging with the information on skin color change made possible through the application of makeups, we were able to develop means by which “youthful appearance” could be optimized.
Using the computer graphics, we were able to demonstrate to a customer the change in facial appearance prior to actual application of makeups.

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