Cosmetic containers have various forms, depending upon their purposes, and are required to have great many functions.
Especlally, quallty malntenance and performance can be given as technical fundamental functions. Because the protectability and the compatibility with contents and function and performance according to their purposes, are essencial to all kinds of cosmetic containers.
However, talking of contents, as there are great many varieties of constituent materials and chemicals for seeking the effect and the efficacy of cosmetics, containers are severely required for physical and chemical characteristics.
On the other hand, many materials and processing methods have been developed regarding also containers in recent years and these developments exert not a little influence on the contents.
Therefore, in this paper, we tried to consider technical experience and knowledge on the relation between the contents and the containers of cosmetics with concrete examples.

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In the view of tyrosinase synthesis, we established the evaluating method for the development of the agents, using mouse B16 melanoma cells. Furthermore, the inhibitory effects of plant extracts on tyrosinase specific activities in culture B16 melanoma cells were examined by using the evaluating method. Achillea millefolium, Artemisia capillaris, Eupatorium fortunei and Polygonum cuspidatum showed the higher inhibitory effects on tyrosinase among plant extracts tested. To clarify the location of the activities in such plant extracts, fractions which were extracted with different solvents such as hexane, ethyl acetate, acetone, ethanol and H₂O, were examined on the inhibitory activity of tyrosinase. Achillea millefolium and Eupatorium fortunei showed the activities in the ethyl acetate or acetone-extracted fraction, and the hexane-extracted fraction of Artemisia capillaris gave the highest activity among all fractions. The inhibitory effects of Polygonum cuspidatum was observed in the ethanol-extracted fraction.

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To develop a new type of quick-drying manicure, we took a different approach by modifying the polymer resin rather than using fast evaporating organic solvent. This was accomplished by grafting silicone chains into the structure of hydrophobic acrylic polymer to create a novel graft polymer which forms non-tacky film. The film retains less high polar solvents upon drying and allows rapid vapor transmission.
The polymer also has a good solubility in many cosmetic oils, including volatile silicone and hydrocarbons. The unique properties of the graft polymer allow many interesting applications in different cosmetic preparations. In manicure applications, the superior properties of the graft polymer make it possible to formulate excellent manicures which are quick-drying, long lasting, safe and comfortable to use.

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Since we have great variation of four seasons in Japan, Japanese skin colors are assumed to vary in an annual cycle. It is our interest to know whether skin colors vary with a change of melanin distribution by the amount of sun light, or vary with a change of skin blood flow by temperature.
Some organisms are capable to predict a coming season by the amount of sun light; therefore, they can make preparations for the coming season. We thus assumed that human beings have a similar “season-predicting program” which makes skin blood flow change according to variation of daylight hours prior to a change of temperature in the coming season.
In this study, therefore, we measured skin colors with a color-difference meter in the 5 seasons in “the Oriental calender” which indicates the variation in intensity of sunlight.
The skin hues obtained at the seven portions over a period of one year revealed annual diphasic changes. Interestingly, inflection points of the diphase change were on the first day of spring and on the first day of autumn.
Annual diphasic changes of skin hue in spring/summer to autunm/winter were observed not only in exposed sites such as a face, but also in non-exposed sites such as the anterior surface of the forearm and the inner surface of the upper arm, This implies that the main reason for skin color variation was the behavior of blood flow in the skin by the change of sunlight amount prior to the temperature change in the season transient perios. In human beings, the season predicting system may remain as it was triggered by a change of the sun amount even though we now spend large parts of our days under artificial lights.
Hue values of the cheek in females changed as well as those in males, but hue values of the forehead in females showed almost no differences between summer and winter. Since skin hues are influenced by cosmetics, menstrural cycles and other factors, further examinations are required.
The present results show that the skin has already become “summer-type” and “winter-type” at the vernal equinox and the autumnal equinox, respectively, in advance of these seasons. From the point of view of cosmetics, we propose that one or two months earlier timing than the current timing for a change of make-up is suitable for a coming season in accordance with the Oriental calendar.

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The tone of makeup products such as foundation (applied color) appears to change after application to the skin. It is well-known that the extent of this change is very difficult to determine before application. Carrently, proper color balance can be achieved only by visual judgment or quantitative color measurement after such products have been applied to the skin. Previously, we reported a method for estimating the reflectance of applied color based on the Kubelka-Munk theory. However, it is not easy to construct the data base needed for estimating the reflectance of applied color. In addition, we found that applied color could not be estimated using this method in some cases.
We therefore reviewed the methodology and procedure used to estimate applied color in an attempt to solve the problems that arose after our last report. In the present report, in addition to predicting changes in foundation tone when applied over normal skin, we examined whether or not this method is applicable to cases in which foundation is applied over blue-black moles (nevus of Ota) or red moles (port wine stain).
Four improvements were made in the procedure. These included: 1) development of a printing machine that enables highly reproducible printing of the foundation coat; 2) modification of the method used to obtain the reflectivity; 3) introduction a software technique that clarifies the relationship between estimated value and the level of the set points K₁ and K₂ in Saunderson's correction formula; 4) introduction of a state-of-the-art laser instrument for measuring the thickness of the foundation coat. Further, using these modifications and improvements, it was confirmed that foundation tone can be estimated for normal skin as well as for the site of moles.

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Since microcirculation of cutaneous tissue plays an important role in the transport of nutrients and oxygen, and in the regulation of body temperature, monitoring the rate of blood flow in microcirculation can indicate the skin condition. However, due to the complexity of blood capillaries and the irregular blood flow of microcirculation, conventional flow rate monitoring may not correctly show the skin surface condition. Therefore, to measure the blood flow in this complex microcirculation, we developed a new probe which can simultaneously monitor the blood flow at a specific point of the skin at six different depths from the skin surface. To verify the usefulness of the probe, we measured the blood flow in various types of skin including healthy skin, dry skin, sensitive skin, reddish skin, flushing skin, skin with hemangioma, and skin with nevous of Ohta. The probe can clearly distinguish a temporary high-blood flow of reddish skin from a normal constant flow visible through the skin surface.

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The objective of this paper is to evaluate the recovery effects of cholesteryl derivatives on the scaly skin. It is recognized that water content of the stratum corneum is the most important factor of the skin softness. In recent studies, stratum corneum lipids have been found to play as the barrier function of the stratum corneum. It has been reported that the scaly skin shows a marked decrease in the water holding capacity of the stratum corneum accompanied by a considerable and selective loss of intercellular lipids such as ceramides, cholesterol, cholesteryl derivatives. We have examined the recovery effect of cholesteryl esters on the scaly skin induced by sodium lauryl sulfate. Their utilities have been determined by water holding capacity using the skin hygrometer, transepidermal water loss (TEWL) using the evaporimeter and so on. As a result, cholesteryl esters have been revealed to act as effective agents for the scaly skin. Furthermore, Acylglutamate Cholesteryl Esters showed remarkable recovery effect of the scaly skin.

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The high-pressure homogenizer has been attracting attention for preparation of fine emulsion and liposome, etc. However, with the presently commercially available equipment, there are problems in such as 1) high energy is consumed because of highpressure, 2) preliminary emulsification is required, and 3) large-scale equipment is required even for laboratory use, resulting in difficulty to use. In order to resolve these problems, a high-performance liquid chromatograph system, which now has reached the maturity stage, is adopted for a pump system, and a new column type chamber which does not utilize cavitation is designed, thereby easily achieving the performance nearly equivalent to that of the existing high-prssure homogenizer without preliminary emulsification under the low pressure conditions. This chamber can be readily upscaled by utilizing the high-performance liquid chromatographic technique, and the use of this technique will enable the construction of a new flow emulsification systen with less dead volume, the level equivalent to that of the flow injection analysis of the chemical analysis technique.

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