Present-day's cosmetic industry is making rapid technological advancements while the country goes through various changes such as increase in the average span of human life, introduction of high technology, and expansion of information networks and globalization.
Many of the recent high-performance cosmetic products take advantage of recent technical advancements in such fields as biotechnology, new materials and formulating technology.
Extensive researches are being made for development of tools and instruments for promotional uses at the cosmetic counter.
These researches are closely related to the life science including dermatological science.
In this presentation, the current status of cosmetic industry will be reviewed together with recent trend in cosmetic technology and themes for the 21st century will also be discussed.

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An attempt was made to obtain informations on the correlation between the rheological characteristics and the sensory assessments for a variety of cosmetic emulsions appeared in the commercially available forms such as milk lotions, creams, massage creams, etc. The flow curve and stress relaxation behaviour of each emulsion sample were measured by means of a cone-and-plate viscometer so as to evaluate the rheological features of the emulsion samples, while the sensory assessments of the samples were made with 10 panels.
The results obtained can be summarized as follows:
(1) A series of the sensory terms defined by use of ordinary expressios on the basis of consistency, spreadability, yield value, and so on for the cosmetic emulsions may closely relate to the rheological parameters of each sample evaluated from the flow curve.
(2) Cluster analysis suggested that the sensory assessments with cosmetic emulsions can be divided into some groups, which correspond to the flow characteristics of each cosmetic emulsion.

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In contrast to the abundant researchs as to the aging symptoms of skin, very little is known about those of nails, beyond the decline in the rate of growth and the appearance of vertical lines. However, many women want their nails to be kept in a healthy and fresh condition, as well as their skin, particularly facial skin. To satisfy this demand, it is necessary to understand various symptoms of nail which appear with aging and elucidate the mechanisms of the changes.
A study was conducted, therefore, in which the changes in nail caused by aging were investigated using SEM. The lipid content in nail was measured by GC, GC-MS, or HPLC, and the moisture content absorbed, the water holding capacity and the strength of nail were determined.
It was found that the nails of people over about ten years showed an increase in the desquamation of corneocytes on the nail surface, a reduction in the content of intercellular lipids such as cholesterol and cholesteryl sulfate, and a decrease in moisture absorption and water holding capacity. Nails in which the lipids was removed using acetone showed a decrease in strength against breaking. The structure and moisture absorption function of such nails were similar to those of aged nails. A correlation was also observed between the content of cholesterol in nail and the moisture absorption function.
From the above findings, it is shown that the decrease in the content of intercellular lipids affects the changes in the morphology and properties of nails seen with aging. Consequently, as in skin care, the healthy condition of nails is considered to be maintained by the supply of moisturizing substances, particularly intercellular lipids.

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O₁+O₂+…/W type emulsion, which we discuss in this article means the cream which the oil droplets with different properties such as O₁ (which has a good sense for skin) and O₂ (which has high mutual solubility with an active component) were dispersed.
The continuous phase of O₁+O₂+…/W type emulsion comprises surfactant (D) phase formed by surfactant, co-surfactant (ex. fatty alcohol) and water, but it is difficult to stabilize O₁+O₂+…/W type because of a movement of each oil through the D phase.
The miscibility between D phase and oil was investigated on the basis of D phase properties, i.e. total surfactant conc., HLB, the addition of water-soluble polymer. As a result, it was found that making the surfactant conc. as low as possible and the addition of water-soluble polymer (sodium hyaluronate, CP (934)-K) with high bound water contents were impotant factors in order to reduce the miscibility and then stabilize O₁+O₂+…/W type. It seems that the addition of water-soluble polymer changes hydration state of D phase, that is, makes HLB of D phase shift toward hydrophilic property.
In addition, it was demonstrated that the sensual evaluation of O₁+O₂+…/W type emulsion was different from that of mix-oil emulsion which O₁ and O₂ mixed each other.
Thus, it was suggested that emulsions combined both various sensual state and stable encapsulation of an active component were expected for O₁+O₂+…/W type.

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The purpose of this study is to clear scientifically the relationship between complexion impression and facial color range on a color space, and to make use of the results on color design of makeup cosmetics and on development of makeup techniques.
A facial picture of a Japanese woman taken with a videocamera was processed by computer graphic technies and 92 pictures with different complexion were obtained. 87 Japanese women's (20-50 years old) impressions (beautiful or not) for 92 pictures were evaluated. Suitable impression words for each picture were selected from several impression words, such as “natural”, “feminine”, “healthy”, etc.
It is found that the facial color range which gives a “beautiful” impression to Japanese women is lighgter, redder and a little vivider than the average facial color of them. Older women prefer lighter color.
The relative position of each word on the Munsell color space was determined.

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The swelling clay is mainly used as the gel agent in cosmetics. In this study, the swelling clay has been applied to the body of the functional powder in cosmetics, taking advantage of its gelation ability and property of intercalation.
The nobel spherical clay was obtained by spray drying the hydro gel of a synthetic hectorite. No swelling clay other than the synthetic hectorite was formed sphericaly in shape by the spray drying process. This is the reason the particle size of this synthetic hectorite is very small, c.a. 100Å, compared with that of the other swelling clay.
Making use of this preparation of the spherical clay, two types of the spherical functional powder have been developed by the way of spray drying the gel of the synthetic hectorite including the various functional material, The first type is the spherical powder containing the functional molecules intecalated in the interlayer of the clay particle. The functional molecules are, for example, moisturizer, perfume, antimicrobial agent, UV absober, dye and so on. The spherical clay intercalating glycerin as the functional molecule has been prepared as the moisutre powder. This powder has a high fluidity even though the amount of glycerin in this powder is 40% by weight.
On the second type of the spherical powder, the fine particle is selected as the functional material. This spherical functional powder contains uniformly fine particles both to the surface and inside of the powder. The fine particles such as titanium dioxide, zinc oxide and ferric oxide, or these colloidal particles can be embeded in the powder as the functional particles. In the case of the titanium dioxide, the surface activity of titanium dioxide has been suppressed because most titanium dioxide particles are embeded in the powder. This spherical powder showed excellent slippage and useability, exhibiting UV protect effect.
These powder will be used conveniently in many cosmetics, exhibiting each function according to the functional material contained.

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Hair luster is one of the criteria to judge the beauty of hair. Therefore, young women are interested in hair luster.
Luster is one of the optical properties. The reproducibility of the data measured optically for hair luster with conventional instruments has been poor and the results obtained have been in less agreement with visual evaluation, because of the influence of color and distortions of hair samples.
Maximal reflection value measured at specular reflection angle (S) and diffuse reflection value measured in the vertical direction to the plane of hair shafts (d) were obtained with goniophotometer on hair tresses with the same luster and different color. “S-d Value” was introduced as “Luster Value” to minimize the influence of color of hair. However, it was not possible to eliminate the influence of color completely by this treatment. Therefore the distribution of wavelength of diffuse and specular reflection was controlled by filters to adjust spectral response of optical detector to relative luminous efficiency curve. By these treatments, the influence of color was eliminated. The incident angle was set at 45° to make “signal noise ratio” higher and the apparatus smaller. Hair holder, which is easy to handle, was developed to keep up parallelism of hair fibers, because disorder of them had considerable influence on the measurement of hair luster.
A handy apparatus, which makes hair luster measurement possible without cutting hair off, is developed. The results obtained correlate to visual evaluation.

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