When we consider what is required of cosmetics in order to effectively enrich human life, We can summarize our research from the point of view of human beings and materials and also from the point of “Hardware” and “Software”.
The “Hardware” aspect of a human being is of course the physical arts of the human body, particularly the skin and hair.
Since cosmetics are directly applied to the skin or hair, it is important to study their physiology.
The “Software” aspect of a human being involves psychology. The positive effect of good cosmetics have on human psychology is already well-known. In particular, the psychological effect of fragrance products (aromachology) and colored make-up cosmetics is great.
It has been discovered that as a result of producing good psychology effects, a very positive influence is made also on the physiological condition of the human body.
As for materials, their “Hardware” aspect is the development of excellent products. Upgrading product quality and attaching a high functionsl element to cosmetics are important research themes.
Studies on the “Software” aspect of materials include the measuring of the specific characteristic of product, physiologically, physicochemically, psycologically and to develop important information regarding prodcts.
Lately, the method for evaluating the efficacy of product has made much progress and has contributed to the development of high functional products.
In this paper, the importance of the interaction between human beings and materials, “Hardware” and “Software” is duscussed, using the study of aromacology and wrinkle-lift as examples.

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The effects and efficacies of cosmetics can be evaluated by human or instruments. Therefore, we can classify those methods into instrumental evaluation and sensory evaluation. Both methods have merits and defects.
Sensory evaluation is important in products development of cosmetics since effects and efficacies of cosmetics are often dependent on individual and are difficult to define and measure objectively.
This report introduces SD-methods and Ohajiki-methods for investigating the quality of lipsticks. Furthermore, Q-Methodology is tested on lipsticks. As a result, we obtained key information from consumers to develop new lipsticks.

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As a qualification factor of emulsion products, particle size and its distribution are important and the method how to control them is important.
The scale-up method of manufacturing process based on such controlling system and using vacuum emulsifying equipment is explained.
In recent years, the formula and manufacturing process being diversifing, it becomes important to find out the balanced point of formula, raw material, manufacturing process and manufacturing equipment. The various emulsifying equipment and agitating blades are introduced.

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Facial scrub cleansers, the cleansing ability of which is raised by scrub particles have been popular recently. However, there are no documents which mention the function of scrub particles. We found by various experiments that scrub particles raise cleansing abilities of the narrow part of skin and have the dispersing and eliminating function of dirt.
We investigated relations between the cleansing ability and physical properties of scrub particles. It proved that the leasticity of particles was required to be more than that of human skin (about 10⁷dyne/cm²) for scrub particles. The size of particles has to be fitted for the skin furrow or hair pores (200-350μm). A certain number of particles are required to maximize its cleansing ability (more than about 100 particles/cm²).
Scrub paticles whose elasticity is similar to that of skin turned out to be appropriately gentle to skin. They didn't damage skin even if we washed our faces every day with a facial cleanser containing the scrub particles.

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Five amino acids (L-lysine hydrochloride, glycine, sodium L-glutamate L-proline, and L-threonine) were used in this study. Their percutaneous absorption from pH 7.4 aqueous solution (PBS buffered saline) were investigated on human cadaver skin. The effects of glycerin, sodium PCA etc. on the absorption of L-proline were also investigated. Amino acids did not penetrate into the reservoir within a few hours but the amounts of adsorbed amino acid in stratum corneum were increased when glycerin or sodium PCA was incorporrated. A negative correlation between flux and log P (n-octand/water) was observed when the amino acid penetration into the receiver solution reached steady state. These resulls suggest not only the possibility of micro channels for amino acid permeation into human skin but also the possibility of incorporating amino acids into skin surface to subserve skin function.

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A new polysaccharide (TPS; Tuborose Polysaccharide) was secreted by callus cells induced by a petal from Polianthes tuberosa. It was found that TPS is useful in cosmetics because it provides protection from external stimuli, which are potentially harmful to the stratum corneum.
When applied on skin, TPS formed a long lasting smooth film. Observation of the TPS film on the stratum corneum cell by electromicroscopy revealed that the flim formed a polymeric fine network structure, covered the rough cell surface perfectly resulting in a new smooth surface. Flexibility and volume of the film were insensitive to different humidity conditions.
When investigating the cosmetic benefits of TPS, it was found that scaling disappeared after application of 0.5% TPS solution on fraky skin. In addition, 0.5% TPS solution seemed to protect the stratum corneum from recurring mechanical stimuli. The application of TPS lotion on the face protected the stratum corneum from dryness during the winter time. The protective effect of the TPS lotion on skin was proven when tested at a ski resort under cold, dry air conditions. These results suggested that TPS is a very useful raw material for skin care cosmetics.

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We have developed a new type of cationic surfactant C 12 A 4G (AG) for rinse out type hair conditioner. In this work, cosmetic novelty, characteristic properties of C 12 A 4G for use in hair conditioner were evaluated and the adsorption behavior of C 12 A 4G onto the hair, the mechanism of this characteristic properties were investigated from the viewpoint of surface chemistry.
C 12 A 4G is the name of an amide guanidine type cationic surfactant having a guanidino group as cationic group (G), an amide-methylene group for 4 methylene groups as spacer between an amide group and guanidino group to boost water holding capacity (A 4) and lauroyl group (C 12). It completely differs from the quaternary ammonium type cationic surfactants currently in wide use now.
The hair treated with C 12 A 4G or hair conditioner containing C 12 A 4G displayed excellent moisturizing effect even in low humidity. The major characteristics of C 12 A 4G were most apparent during rinsing when used in hair conditioner. This conditioner was able to increase smoothness of the hair to levels never before attained and made the user the feel that it was retained on the hair, leading to consumer confidence in the perceived damaging free effect of the conditioner. The characteristics of C 12 A 4G derive from its molecular structure and the aggregates with cetyl alcohol. We clarified the adsorption mechanism of C 12 A 4G onto the hair and analyzed the aggregates formed by C 12 A 4G and cetyl alcohol using DSC, ESR technics. The results suggested that C 12 A 4G highly adsorbed onto the hair and these aggregates possessed grater water holding capacity than conventional ammonium types. It is considered that these characteristic aggregates display unique conditioning functions when they work on the hair.
Moreover the safety test of C 12 A 4G was very good. In the near future C 12 A 4G certainly promises to displace quaternary ammonium types used in hair conditioners.

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The authors have developed an instrument for instantaneous, non-contact measurement of the three-dimensional morphology of wrinkles on human skin to determine transient changes in the shape of wrinkles and changes in the skin surface microtopography after application of an anti-wrinkle agent. When such measurements are made, it is usually impossible to record shape changes accurately over time unless the geometrical position of the target skin region is precisely defined. Generally, when measuring wrinkle shapes in the same individual at different times, it is difficult to locate exactly the same target skin region at every measurement session, even with the greatest of attention. As a result, image dislocations can occur. Such dislocations are caused when the region to be measured is shifted relative to the X-/Y-axes of the observation system, or when the region is rotated, enlarged, reduced or subjected to local distortion caused by any of a variety of uncontrollable factors. It is impossible to define markers at multiple positions in the target region to aid in the repositioning of the observation system. Consequently, it is difficult to correct for any enlargement, reduction and/or distortion that might have occurred in the target region.
By limiting the target region to a small area with wrinkles to which comparison and reference can be made, the authors developed a technique for correcting rotation and/or dislocation errors. We also introduce a new method in order to compare and reference the changes in wrinkle shapes observed in measurements made at different times.

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