Emulsions have been widely used in the fields of cosmetic, food, pharmaceutical, agricultural chemicals, paint, and so on. Therefore, a lots of works have been published on the problems of emulsion.
When one of the liquids is water and the other is water insoluble or “oil”, two types of emulsion are theoretical possible, depending upon whether oil is dispersed in water O/W, and or vice verse W/O.
After an emulsion has been formed the emulsifier is absorbed in considerable part at the drop interface, where it has to form a curved film.
The chemical nature of the emulsifying agent is the most important factor in determining which of two liquids will be disperse phase and which is continuous, at one, least in the most widely investigated gamut of systems, “oil” and “water”.
The purpose of this paper is to provide information to emulsion and surfactant scientists on how logically and readily microemulsion, emulsion stability, are depend on the chemical structure of surfactant.
The description will cover normal and inverse micelles the hexagonal and lamella liquid crystal will be mentioned only in connection with the phase in equilibrium with oil-surfactnt-water systems.
The presence of liquid crystalline and gel structure will give an enhanced stabilization to the emulsion and also change its reheological properties.

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Some physicochemical technics which have been developed in the decade of 1980s for preparing fine oil-in-water (O/W) emulsions are summarized in this article. The characteristics of emulsions prepared by HLB temperature methods microemulsion method, phase inversion method, D phase method and liauid crystalline method are reviewed. The emulsification mechanism of these emulsifing technics is also described. Suitable nonionic surfactants for preparing fine emulsions are also discussed.

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We studied the effect of a fragrance on stress, paying attention to the frequency fluctuation and cycle variances of α-waves in EEG.
Four healthy subjects, ranging in age from 22 to 39 years, participated in the experiment. The EEG was recorded, keeping eyes shut and seated, from Fz, C3, C4, Cz, and Oz scalp location, reffered to linked ear lobes for 5min during blank (rest), 2min during stress (verbal task: backward recitation of 4 figures number), 5min during fragrance preseentation (environmental fragrance “D” citrus mint note developed by POLA. α-wave component (8-13Hz) was extracted using a degital filter and the frequency fluctuation was analyzed using “Power spectrum” method. Cycle's variances (msec) were calculated every for 5 seconds and plotted.
The frequency fluctuation with a fragrance showed more 1/f type over lower frequency than that without one, and the larger was the change of cycle variance, the bigger was the degree of 1/f type.
Except the case when this fragrance is rather strong to a subject or given stress only by participating in the experiment, we suggested that a pleasant fragrance reduces stress. However, as it is considered this effect may occur independent of the taste of odor, it is necessary to be examined by not only a good odor but also a bad one.

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Human skin surface has been analyzed in situ after washing with fatty acid soap by attenuated total reflectance using Fourier transform infrared spectroscopy. The residue of fatty acid soap on the skin was observed when calcium ions were present in the water being used, and it was confirmed to be adsorbing onto the skin as fatty acid calcium salts. This adsorption residue was quantified using the Amide I or Amide III absorption bands of the epidermal horny proteins as an internal standard.
The behavior of adsorption residues has been examined with this method, and it was confirmed that the quantity of adsorption residue increased depending on the calcium ion concentration in the water. Furthermore, it was suggested that the adsorption residue was induced by the insoluble salt formation from fatty acid anions adsorbed onto the skin and calcium ions at the time of rinsing. Fatty acid calcium salts adsorbed onto the skin were gradually desorbed by sufficient rinsing, but the influence of calcium ions was also seen in this case. This desorption speed was slower when calcium ions were present.

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Fragrance materials such as perfumes have long been known to exert effects on the mind and body. Throughout histry, perfumes have been used as sedatives and stimulants. However, there are very few psychophysiological studies in aromachology with regard to the effect of odor itself on human subjects.
In this study, the effects of odors on cardiac response patterns were investigated during the foreperiod of the two-stimulus paradigm in a simple reaction time task. Changes in the cardiac response pattern were typically triphasic during the foreperiod between the worning stimulus (WS) and imperative stimulus (IS).
Heart rate decelelation (DE) usually seen just prior to IS is thought to reflect the process of anticipation or attention. Thus, stimulative odors are expected to activate those processes while sedative odors are thought to exert a suppressive effect.
This experiment was designed to estimate the effect of some kinds of odors by the DE amplitude. Olfactory stimulation (some different aromatic air samples and odorless air) was provided to subjects by the blast method.
A trial consisted of a 5-second rest period, followed by a 20-second period in which the olfactory stimulus was presented, a 10-second foreperiod lasting from the WS tone to the IS tone signaling the subject to press the response key, and a 15-second post-foreperiod after the IS tone.
The odor of lemon, traditionally thought to be stimulative, had the effect of activating anticipation or attention process. This effect tended to be stronger by increasing odor intensity. On the other hand, the rose odor, thought to be sedative, had the effect of suppressing this process, and these effect was observed across all intensity levels.
Futhermore, We carried out an experiment in the same method, to estimate the effects of 3 kinds of perfumes for the development of odor using for certain skincare products.
We believe this investigational method with two-stimulus paradigm could be a useful one to determine the psychophysiological effects of odor especially in stimulative-sedative continuum of its effect.

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To evaluate skin color and skin tone exactly, we developed a new instrument, Skin Tone Analyzer (STA), which applys an image-processing system on the polarized images of skin.
The insertion of two polarized filters into the CCD camera in STA made the observation of clear images without interference from the diffuse reflections originating on the surface of the skin. The 20 times magnified images of the skin surface (1×1cm) are resolved into 400×400 points and transfered to a digital computer. To measure the color difference value, calculate the L, a and b values of each point from their respective R, G and B values, using conversion equations determined from the measurement of two hundred pieces of standard color papers with the STA and general spectrophotometric colorimeter (CMS-1200). Then, the color differences determined by STA are indicated as average values of L, a and b values for a finite set of points. Further, their standard deviation values (s. d.) which may represent the degree of skin tone (irregularity in the lavel of skin color) are obtained. In fact, we found that the s. d. of b values (s. d. b) among the three components, L, a and b, reflects appropriately the degree of skin tone caused by delocalization of melanin. Thus we now propose that the s. d. b is a good parameter for the evaluation of skin tone. Moreover, a designated part of images can be analyzed and STA will be a useful tool for the study of pigmentation spots.
Based on the above assumption, we examined the effect of seasons and aging on the skin color and skin tone of the cheek (exposed skin) and the inside of the upper arm (non-exposed skin) in healthy Japanese females (N=62, 19-75y) with STA. From the analyses of skin tone during periodical measurements, the degree of skin tone in the cheek was found to be worse than the arm's. The former becoming worse owing to aging, but the later exhibiting no change. Also the degree of skin tone in the cheek in October (after the summer) was worse than in February (in the winter). In addition, L and b values for the cheek also increased owing to aging, but these values for the arm did not so change.
It is known that daily exposure to ultraviolet rays (UV) can influence colory skin. We now also confirm that UV promotes a change for the worse in the skin tone. Next, we propose to study the effects of UV on localized pigmentation using STA.

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In contemporary society which is composed largely of elderly people, “Aging” is a significant problem. Thus, research into anti-aging has become popular in various fields. In this context, cosmetic products are expected to prevent skin aging. Wrinkles are one of the typical symptoms of skin aging which is caused by functional weakening and structural change in the dermis. The activation of dermal cells is one of the major methods used against wrinkle formation.
Recently, there has been a great deal of research done about the cellular activator which comes from animals or plants. In particular, the materials from the bovine are much used in cosmetic products. We have done research on bovine brain components for cosmetic products and found that the lipids contained in the bovine brain are effective at holding water in the horny layer of the skin.
In this paper, we report the effect of the bovine brain extract on the fibroblast synthesizing the collagen and acid mucopolysaccharide, which are the major components of the dermis.
The effect of the bovine brain extract was estimated with three methods; the cellular activation effect using the MTT-method, the collagen synthesis and the proliferation of the skin fibroblast. The results of these tests demonstrated that the bovine brain extract caused the activation of fibroblasts. A detailed analysis of the results revealed that the peptide fraction was effective on the collagen synthesis and the phospholipids on the proliferation of fibroblasts. The fraction containing phosphatidyl ethanolamine separated from phospholipids in particular has a great effect on cell growth.

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