The method of microencapsulation of cosmetic oils was studied. As the wall material, poly-acrylic esters, polymethacrylic esters and polyvinyl acetate were chosen.
Among the investigated method of encapsulation, most suitable one was the in situ polymeri-zation directly on the surface of nucleous oil particles which are dispersed by using synthetic clay as dispersing agent.
With this method, hydrocarbons and silicone oils were encapsulated easily, but each one of fatty acid, long chain alcohol, viscous oil, and caster oil was not encapsulated singly.
Fragility of capsule wall against force of rubbing on the skin depended mainly on the content of encapsulated nucleous oil.
The microcapsule of liquid paraffine with capsule content of 75% by weight was not broken even when it was compressed up to 50kg/cm² pressure. However same microcapsule was very fragile against shearing force. When the microcapsule was put between two slide glass and slide glass were slipped each other under virtical pressure of 10 to 40g/cm², it was broken entirely.
The microcapsule was durable against processing forces such as stirring, for example 10000rpm, 10 minutes.
There was no leakage of nucleous oil after microcapsule was kept at 80°C for 5 hours in aqueous solution of sodium lauryl sulfate. Neither swelling of capsule wall nor leakage of nuc-leous oil took place after microcapsule was kept in the aqueous solution of typical surfactant for 2 months.

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Some physical properties of acrylate resin balloons were compared with extender pigments. Acrylate balloons were prepared through the process of in situ polymerization of W/O/W emulsion.
The angle of fall and the angle of repose were measured in order to evaluate the spreadability of acrylate balloons and extenders when they are applied to the skin. From the relation between the angle of fall and the angle of repose, extenders are classified in three groups. Each group of extenders is characterized with their particle shape such as spherical or platelike. Acrylate balloons are located out of the range of these three groups because of their low angle of fall and low angle of repose.
It was also shown that not only the particle shape but the structure of the particle surface has affected the spreading behavior of extenders on the skin.
The oil absorption value of acrylate balloons was adjustable, to be lower than that of silica beads but higher than that of the other extenders, by changing the amount of surfactant used in the polymerization process.
The transparency and the air permeability were also measured. Due to the porous baloon particle structure, acrylate balloons were less transparent than acrylate beads, but more transparent than nylon powder.
The air permeability of acrylate balloons was almost twice times larger than that of the other spherical extenders. Porour balloon structure of acrylate ballons appeared to be effective to provide high air permeability.
The result of water absorption study suggests that acrylate balloons have the moisture control capacity when they are applied to the skin. Acrylate balloons absorbed water in high humid air and released water to dry air reversibly. The amount of water held in acrylate balloons was much larger than that of silica beads, and the balloons absorbed less water in the low humid condition as compared with silica beads.

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The effects of increased calcium content in hair caused by coldwaving on the mechanical nature of the hair were studied. It was revealed that the heavy sorption of calcium ion to the hair made its rigidity increased.
The sorption behavior of calcium ion to the hair was also investigated. Namely, the distribution of the ion in the hair was examined by electron probe microanalyzer. The influences of pH of the bathing solution and the chemical modification of the hair on the sorption were studied. The results indicated that calcium ion penetrated into the hair cortex, as well as adsorbed on the hair surface, and that the sorbing site was mainly the dissociated carboxyl group of the hair keratine. Furthermore, to elucidate the cause of the high calcium uptake of the permed hair, the sorption isotherm and the sorption rate were investigated. The both results obtained implied that the high calcium uptake of the permed hair was derived from the increased difussion coefficient of the ion into the hair, and from the increase of the dissociated carboxyl group.

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From archaeological evidences, many of authorities believe that the history of cosmetics can be traced back to 40, 000-50, 000 years ago. However, since ancient Egyptians and Mesopotamians protected their skins with cosmetics against scorching, I propose a hypothesis that the ancesters of Hominies had applied spontaneously a mass of mud or clay on their skins for protection, when their hairs had begun to degenerate from bodies.
In this paper, I will discuss the hypothesis through following problems:
1. Why the ancestors needed protection?
2. Why had the body hairs degenerated and when it had occured?
3. With regard to applying or wearing as the method for body protection, which took place first?
4. What had they applied?

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