Accurate measurements of hair luster on the head (HLH) in situ is not an easy task and no satisfactory method is available at this time.
A new instrumental analysis method called “Color Image Analysis” was developed in this study to overcome the problem. In this method, a ratio of mean brightness in the highlight and adjoining dark portion of the hair image is computed from blue and red color signals. The result was much improved correlation with visual observation, compared with formerly used goniophotometry, since our HLH data included elements of micro-surface condition, macro-state as well as color.
Using this method, effects of changes in the state of hair and usefullness of hair-care products were investigated. We obtained interesting results on the effects of hair-luster preparations and hair coloring. It was clear that our method could be used to accurately determine the difference in hair luster.

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Microcapsules are minute containers in which individual entities of a solid, liquid, or gas are discretely enclosed, with shells made of natural or synthetic materials. These shells may be designed to protect from their environment, to aid in the storage, or to release their contents at specific rate or under a specific set of conditions. In the applications of microcapsules to cosmetics (particularly to cream), it may be necessary for microcapsules to have the following requirements; 1. the transparent shell film 2. the easy preparation process 3. insolubility in water or other solvents 4. easy breaking of shells on the palms of the hands upon usage 5. the composition of the innocuous ingredients for a human body. The shell materials and the preparation methods were studied to satisfy the above requirements. The most suitable microcapsules were prepared by a complex coacervation methods involving a phase separation in a gelatin-acacia mixture in aqueous phase. Their shells were composed of the crosslinked gelatin. Glutaraldehyde was selected as the crosslinking agent to denature gelatin into an insolble substance in water or other solvents. The particle sizes of the developed microcapsules were controlled by the stirring rate on preparation or the polarity of the oil enclosed within. Also, the breaking strength of microcapsule was controlled by mixing a liquid and a solid oil component in the suitable ratio. The stabilization of fragrance, vitamin A palmitate and ethyl linoleate was tried by microencapsulation in order to protect the enclosed materials from their environment. Microencapsulated substances showed an excellent in stability compared with emulsificated substances. Further, a more excellent stability could be exhibited by increasing the shell thickness of microcapsule or modifying the microcapsule's gelatin film by poly-lysin. From the measurments of the oxygen permiability coefficient of the plane modified geratin film, it was supposed that the fine matrix composed of gelatin and poly-lysin prevented the oxygen permeability and this gave an excellent stability.

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From a viewpoint that disulfide bond (S-S stretching vibration) demonstrates the considerable strength of Raman activity, the (-S-S-) bond in hair treated with the permanent waving agent was studied by Raman spectroscopy. It was found that even with a singlehair a favorable Raman spectrum can be obtained for a white hair, though not for a black hair. It was confirmed by the Raman spectroscopy that the band intensity of hair, at about 510cm^-1 based on the (-S-S-) bond, reduced apparently upon treatment with the permanent waving agent 1st solution and increased again by treatment with the permanent waving agent 2nd solution to the former level.
It was feasible to examine the (-S-S-) bond of hair quantitatively by calculating a ratio of band intensity based on the (-S-S-) bond against that of amide I based on the peptide bond as the standard, (510cm^-1)/(1665cm^-1). Raman spectroscopy which requires no troublesome pretreatment has shown that the degree of reduction or degree of recovery of the (-S-S-) bond of hair obtained for a series of the cold permanent waving agent models was in good agreement with previously reported results obtained by the determination of cysteic acid residues with amino acid analysis and/or infrared spectroscopy.
It was confirmed that the waving efficiency under treatment with the permanent waving agent and the degree of reduction of the breaking strength per sectional area of hair were influenced by the degree of reduction of the (-S-S-) bond under treatment with the 1st solution, and that with increasing the degree of reduction of the (-S-S-) bond of hair under treatment with the 1st solution, the waving efficiency became higher and the degree of reduction of breaking strength per sectional area of hair became larger.

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Almost all women have a desire to maintain smooth and soft hands. Particularly in Japan, where “dry chapped hands” is a great nuisance for women in their daily life, and an important problem which cosmetic scientists should solve. The purpose of this study was to clarify the process whereby the hands become dry and chapped, and to develop the preventive cosmetics for it.
Our survey showed that the skin was most chapped on the thumb, index finger and middle finger and in the upper extremities of the fingertips. The characteristics of dry, chapped fingertips were investigated through methods of dermatophysiology and histopathology (scanning and transmission electron microscopy etc.). It was found that the functional damage of sweat glands and parakeratosis were important key points with respect to the onset of chapped fingertips.
In order to examine dry chapped fingertips in detail, a method of counting the number of active sweat glands was developed to evaluate their function objectively. Also, quantitative methods using image analysis of microscopic patterns of fingerprints and amount of scales, were developed as objective evaluation of parakeratosis. These new quantitative methods helped the study to find ways to prevent dry chapped hands.
In the course of the studies described above, effective substances and methods to protect corneum cells and sweat glands from the damage of detergents were investigated. These studies showed that condensed tannin extracted from persimmon (Diospyros Kaki Linn.), forms a protective membrane on the fingers and sweat gland walls, and it is remarkable in preventing skin from becomming chapped. Subsequently, stabilization of persimmon tannin against oxidization and heat was successfully achieved. It was concluded that persimmon tannin is an effective in-gredient for daily hand-care cosmetics.

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