Paints are mainly consists of pigmens, resins and solvents. As for the design of paint formulations, especially of mill base formulations, it is important to consider how to stabilize the dispersed states of pigment. In the practical paint systems including both of solvent and water borne paints, steric stabilization by resin adsorption on the pigment surfce is necessary.
The driving forces of resin adsorption in solvent and water borne paints are acid-base and hydrophobic interactions, respectively. Pigments and resins must be chosen in mill base formulaions so thatt hose strong interaction take place. Characterizing methods of acid/base and hydrophilic/hydrophobic properties of pigments and resins are briefly reviewed. The chracteristics of pigments and resins are correlated with the pigment dispersibility.

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Lipstick, used by almost all Japanese women, is the most important product of makeup cosmetics. Sales of lipsticks have increased year by year because of their innovative development.
In this paper, the differences between skin and lip, troubles with lip, the required functions for lipsticks, treatment effect, texture, luster, coloring materials, perspiration and long-lastingness are described.

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The determination of water-soluble polymers in toothpaste is highly important for the analysis and the quality control of the products, because the water-soluble polymers dominate the performance of the products.
We improved method for determining the water-soluble polymers in toothpaste by means of FT-Raman spectrometry. Its measurement method is similar to FT-IR's one, and measuring operation is simple and speedy. The measuring time is only 15 minutes to one sample.
It was confirmed by FT-Raman spectrometry that each typical water-soluble polymers, i.e. sodium carboxymethylcellulose (CMC), carrageenan, hydroxyethylcellulose (HEC), xanthan gum, sodium polyacrylate, showed some characteristic peaks. They were applicable to the qualitative analysis thereof, and we did not need troublesome data analysis.
The calibration curve obtained in terms of peak-height ratios at 856cm^-1 (carrageenan) vs at 936cm^-1 (CMC) showed a high linear relation curve. We could calculate simply and quickly mixture ratio of CMC to carrageenan by the calibration curve.
The pretreatment methods for separate water-soluble polymers from toothpaste were only easy solvent extraction and dialysis, because FT-Raman spectrometry is little interfered by some impurities.
We applied the analysis procedures to 4 tubes of test toothpaste. The result was that they analysis procedures was proved to be effective and reliable in analyzing the commercial products.

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To establish an in vitro method for measuring SPF with a high correlaion to in vivo SPF, it is important to understand all he biological phenomena and effects in terms of the eryhemal response o UV light. Our research focuses on the problem of he synergisic effect of UVA on the biological acivity of UVB. We invesrtigated the UVA-promoter action using spectroradiometric measurement of the UV transmittance with and without the sunscreen applied and in vivo SPF values presented in the Federal Register OTC Monograph (1978). We analyzed the effective intensity by multiplying the transmitted UV spectrum of sunscreens by the biological effectiveness for the erythemal action spectrum, estimating the transmitted UVA of sunscreens, and confirmed the UVA photoaugmentative effect related to the erythemal response. We also confirmed that this photoaugmentative effect is affected by the UVA/UVB ratio in relation to the synergy between UVA and UVB. When we applied the equations obained form these results to various sunscrees, we obtained a very high correlation with the in vivo SPF values. In addition, by using the correlation obtained form these equations, we have been able, for the first time, clearly determine the regions where the erythemal response related reciprocity does and does not apply. The occurrence of a non-reciprocity region where reciprocity does no apply, suggests the other biological factors are important. We can forecast SPF values up to the high-SPF region at much higher accuracy than achieved previously by using the SPF equations while taking these unclarified biological factors into account.

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A face beautifully made up with foundation may appear perfect to the naked eye; it will often appear unnaturally pale-white on photographs taken with flash cameras. Basically the problem is caused by poor photographic technique; however, consumers often blame their makeup for the disappointing pictures. It is a serious problem in Japan as surveys indicate that over half of all users have experienced this problem.
This photographic whitewash effect is worst when foundation is applied heavily and when the flash photograph is taken with a compact camera having small light output. By studying the spectral reflectance of faces made up with foundation, while taking into account the color-reproduction characteristics of the films, the mechanism of this effect was investigated.
This understanding of the basic mechanism allowed us to develop pseudobrookite powder by sintering the two pigments, titanium dioxide and iron oxide, to form Fe₂TiO₅. Incorporating this powder, we developed a new type of foundation which completely eliminated whitewash effect under all lighiting conditons.

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2, 3, 5, 6-O-tetra-esters of L-ascorbic acid (fatty acid: 2-ethylhexanoic acid, 3, 5, 5-timethylhexanoic acid, isopalmitic acid, isostearic acid) have better performance, such as;
1) They are colorless clear liquids and almost soluble in oily materials.
2) They are thermally stable without deterioration in color
3) They are very safe materials.
4) The stability of the pigment dispersion (tianium dioxide, zinc oxide, calcium phosphate hydroxide) is favorable.
5) They have the high moisture permeability.
6) They have SOD-like activites.
7) They are casily obtained without protecting the L-ascorbic acid or the derivative thereof such as 5, 6-O-isopropyridene-L-ascorbic acid.
Therefore, a new type of application for cosmetics has been derived from 2, 3, 5, 6-O-tetra-esters of L-ascorbic acid with these desired properties.

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In order to analyze the diagnosis information of the physiological human skin condition, a series of tactile and visual evaluation were carried out on the cheeks of 20 panelists by an expert. The corvariances among each evaluation items were examined and two factors, a texture factor and an elasticity factor, were derived. Next, with the view of the estimation of product performance of cosmetics, a measuring device equipped with a robot arm and linear actuator was developed, in order to realize mechanical methods derived from tactile perception models.
This device was applied to evaluate effects of continuous usage of a series of facial treatments. The viscoelastic parameters were derived and the measurement was applied to cheeks of 20 panelists. The significant effects of elasticity were proved after five times of a facial treatment for a month in the higher aged panelists. Next, physiological skin conditions after usaged of emulsions were discussed. Four types of emulsions were used for cheeks of four panelists. Friction forces were measured and from the data analysis of each measurements, the changes of skin surface conditions related to sensory properties of emulsions were detected.

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We developed a new evaluation system (Shiseido Wrinkle Analyzer 3 D Pro) for the analysis of facial wrinkles. This system enables us to obtain precise three-dimensional information based on the curved shape measurement. Using this system, we can quickly classify the wrinkles at the corner of the eye “crow's feet” into coarse or intermediate wrinkles and fine wrinkles.
Three-dimensional curved shape measurement was performed by laser slit beam scanning which is capable of measuring the configuration of the objects on a noncontact basis using skin surface negative replicas. Parameters were collected for the depth, width, length, area, volume and line/base etc. Analysis was based on the three-dimensional inverse Fourier transform of the power spectrum obtained after filtration of the data from the three-dimensional Fourier transform of three-dimensional coordinate of the replica. One of the advantage of this method is the capability to extract and synthesize the image of the parameter group.
This system was applied for the quantitative analysis of wrinkles in association with aging in 275 skin surface negative replicas of the “crows feet” site in Japanese females ranging in age from 20 and 79 years. Data clearly revealed that the wrinkles could be extracted from the other three-dimensional data. In addition, it was confirmed that most of the coarse of intermediate wrinkle parameters gradually increased with age, while the fine wrinkle parameters increased up to the middle age and decreased thereafter. These results suggest that the formation of coarse or intermediate wrinkles must be caused by different mechanisms than that of fine wrinkles.

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We have been using a GC/MS as a main instrument of perfume analysis. However, a mini-computer with our previous system wasn't able to calculate area% of peaks, so that we had to use other instruments to calculate it. In other words, we weren't able to modify data and compare with each data at the same time, it took time for system to put data out.
In the present study, we introduced a GC/MS data analytical system (PC-LAN system) that enabled us to search and edit data using a external PC in a simple and quick way. It was established in this system that all data were modified with a PC alone. Moreover, several PCs connected with this system provided us simultaneous analyses of some samples at the same time. The newly established system also prompted a library search.

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It is well known that hair growth is regulated by many factors. In the male pattern baldness, the hormonal effect due to androgens, such as testosterone (TE) and dihydrotestosterone (DHT), is the most important factor. TE is converted to an active androgen, DHT, by 5α-reductase. It has been considered that the DHT binding to androgen receptors expresses the hormonal effect. Therefore, we searched for active ingredents which possessed 5α-reductase inhibitory activity among 80 kinds of plant extracts. We found that Hop (Humulus lupulus L.) strongly inhibited the activity of 5α-reductase. Furthermore, it was found that Hop extract enhanced the proliferation of hair follicle derived keratinocyte. We demonstrated that Hop showed a potent stimulation of hair growth in the animal tests as well as Minoxidil. Hop extract gave the increase of the hair growth rate in human use test. Finally, the effect of the Hop extract was evaluated by using the 54 volunteers suffering from androgenetic alopecia. Most of the volunteers answered that the tonic was effetive in hair repairing.
We conclude that Hop extract is an excellent ingredient for hair growth products and that hair tonics containing Hop extract can benefit people suffering from androgenetic alopecia.

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Toothpaste formulae having the ideal rtheological property without inactivation of cationic antimicrobials such as cetylpyridnium chloride and chlorhexidine digluconate were developed and investigated.
Experimental tothpastes containing polyquaternium 10 (M. W. 2 million) or a high concentration of poloxamer 238 as a gelling agent were prepared. As a control, the toothpaste containing celulose gum that is anionic polymer was also prepared. All these tothpastes contained a cationic antimicrobial agent.
The bactericidal activities were retained in experimental toohpastes consisting of polyquaternium 10 or a high concentration of poloxamer 238 but not retained in the control tothpaste consisting of cellulose gum.
A non-Newtonian index, which had a positive correlation with pseudoplasticity, was introduced for evaluation of the rheological property. The indices of the above mentioned experimental toothpastes were higher than those of the control toothpaste and showed little change in spite of a change in viscosity.
Furthermore, in the delivery of cationic antimicrobials to saliva-coated hydroxyapatite disk, the toothpaste consisting of polyquaternium 10 was superior to that consisting of poloxamer 238.

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