This was done to establish an analitical method for halogenated bisphenol antimicrobials in cosmetics. The primary problem is to find cleanup methods which make the test solution an adequate one for gas chromatographic analysis.
For this purpose, polyamide column chromatography was applied. Antimicrobials were recoveried 95-99% from polyamide column.
In commercial samples, hexachlorophene beyond the permissible level was found, but bithionol and dichlorophene were not.

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Amino acid is one of important elements which are hygienic beauty agents to the skin and hair.
To utilize the character of amino acid to cosmetics in various aspects, authors esterificated Nacyl acidic amino acid, N-long chain acyl neutral amino acid and pyroglutamic acid with various Kinds of alcohol, and studied on application of their ester compounds to cosmetics by using the method for the emulsifying of organic compounds in the organic conceptional diagram.
As a result of these studies, it has been found that amino acid ester compounds have the superior properties as oil soluble raw materials and surfactants.

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Toothpastes which are considered to be concentrated suspension, are consisted of fine solid particles (abrasives), water soluble gums (binders), surface active agents, polyol (humectants), water and others. Only a couple of papers on rheological properties of toothpastes have been published so far, furthermore those results have not been used effectively in practical production of toothpastes. The difficulties of rheological studies of toothpastes are that, (1) they belong to quasi-stable system (2) they are highly concentrated suspension and contain a lot of fine solid particles, and (3) they are so-called multi-components suspension system. For present study, rotational coaxial cylinder viscometer (Thixotrometer) was used to characterise the rheological properties of the water soluble gums, such as carboxymethyl cellulose and carrageenan.
Their flow curves were analysed by means of power law equation, and the discussions on their flow constants such as K and γ on activation evergy were made. Both samples showed pseudplastic flow, however carrageenan had more complicated flow characteristics than carboxymethyl cellulose. Non newtonian index, γ, of carrageenan ranged 0.19-0.38 and that of carboxymethyl cellulose 0.40-0.66 respectively. The analysis of non-Newtonian index, activation evergy, dynamic modulus and dynamic viscosity indicated that carrageenan had more complicated structure than carboxymethyl cellulose.

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The essential oils made from citrus fruits are often used in the compound perfumes for cosmetics, and they cause photodermatitis sometimes. The typical examples are bergamot oil, lemon oil, lime oil and grapefruit oil. The phototoxitic reaction is due to some furocoumarins (5-MOP, 8-MOP, etc.) contained in those oils. UV absorption spetcrums of the furocoumarin group are observed at approximately 320nm. We examined the relation between UV absorption at 320nm and the result of actual photopach test on human skin by exposure to xenonlamp and sunlight. The authors found the fact that the citrus oils showing UV absorption at 320nm will have posibility to cause photodermatis. When we use genuine citrus oils for skin cosmetics, we must take care of the quality of them. Now, we can get some refined citrus oils and synthetic ones without the photosensitic substances that show UV absorption at 320nm. If we use them, the problem of the phototoxity will be avoided.

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Softness of human hair plays a big roll on the manageability of it. Therefore, it is important to measure the softness quantitatively. It is well known that the softness of long shaped materials can be obtained from tensile young's modulus and bending modulus. The tensile young's modulus is most generally empolyed as a parameter of softness, but is usually obtained by destructive way. Bending elasticity can be obtained by nondestructive way and is suitable for the study of the natural materials with scattered properties such as hair. But accurate measurement on hair bending may be difficult because of its hygroscopy and curl, and there is little informations about the bending of hair within authors' knowledge. In this paper, the bending length measurement, which is one of the possible way to measure the bending elasticity, is applied to study the softness of hair. The increased bending length with the enviromental humidity is arised from the increase of the bending elasticity and that of the weight caused by the absorption of water, and the latter can be reduced by peirce's equation. The effect of curl can be minimized by the average of the bending length's of two opposite situations along the axis of the hair. As the result, the softness of hair is obtained with good accuracy by means of the bending length.

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The hair applied oils such as hair cream and hair oil feels supple, soft and manageable. In this paper, the change of the softness (flexibility) of oil coated hair accompanied with the change of enviromental humidity is studied by means of the bending length measurement. The effect of oils on the softness is compared with that on vapor permeability of its film. Resultingly, it becomes clear that the oil whose permeability is small keeps the large softness of moistened hair in dry atomosphere. And it is concluded that the oil on hair affects not only on the friction and tackiness of hair surface but also on the softness (flexibility) through the medium of water vaqor loss.

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