Fabric quality has been subjectively evaluated by consumers and textile producers by means of the hand touch of a fabric. The physical properties of a fabric also have been investigated objectively. In this paper, four evaluation methods are introduced to investigate the relationship between objective and subjective evaluations which closely related human feeling. Firstly, the most well known procedure is the fabric hand evaluation system. This analysis has been applied to the development of new fabric design and the quality control during the production process. Secondly, the simulation method to describe the stickiness by water between lingerie fabric and skin is introduced. Thirdly, characteristic values of surface smoothness of the cosmetic sponge is presented to predict the subjective “smoothness” which occurred when the cosmetic sponge was rubbed against the skin. The effect of fiber properties on the performance of wadding is investigated for the compression properties for various wool fiber wadding.

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The hair follicle is composed primarily of epithelial and dermal components which develop from embryonic ectoderm and mesoderm respectively. Hair growth cycle as well as hair follicle morphogenesis are coordinated and complex processes that are dependent on the interactions of epithelial and dermal components. Over the past decade, many genes such as hairless, nude, sonic hedgehog, β-catenin etc. have been identified as morphogenic molecules, and several gene families are particularly important to hair cycle control, namely, TGF-β, FGFs, IGF-I (insulin-like growth factor-I), and EGF families. EGF receptor signaling has been found to play an important role in catagen induction by the experiments of transgenic mouse models. STAT 3 is a down stream signaling molecule of cytokines, growth factors including EGF and HGF. Conditional gene targeting of STAT3 in mice showed severely compromised hair cycle and wound healing processes. Growth factor-dependent in vitro migration of the STAT3-disrupted keratinocytes was impaired despite normal proliferative responses. STAT3 plays a crucial role in skin remodeling, that is, anagen induction and wound healing. One of the typical example of the signal transduction in the cell is androgen-androgen receptor system. Androgen receptor, ligand dependent transcription factor, is apparently involved in hair cycle control in human. Beard, axillary and frontal scalp dermal papilla cells (DPC) strongly expressed androgen receptor mRNA. While the expression of type I 5α-reductase is ubiquitous property of DPC, type II 5α-reductase gene expression is limited to beard and frontal scalp DPC. Androgen significantly stimulated the proliferation of follicular epithelial cells cocultured with beard or axillary DPC, suggesting that these DPC produce androgen-dependent diffusible growth factors. IGF-I was identified as one of the androgen dependent paracrine growth factors in DPC. On the contrary, frontal scalp DPC of stumptailed macaque inhibit the growth of follicular epithelial cells in an androgen dependent manner. It should be clarified whether inhibition or production of growth factors inhibitors are involved in these effects. Finasteride that is a potent type II 5α-reductase inhibitor is a new treatment for androgenetic alopecia and minoxidil is currently avairable in Japan. New approach to control transcripitonal activity of genes involved in hair cycle will extend further treatment options.

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Glycosidically bound volatiles (GBVs) have been known as fragrance precursors in essential oil plants, but little attention has been paid to them as cosmetic ingredients. In this study, we investigated the possibility of GBVs as deodorant ingredients. After incubation of skin microflora with various kinds of GBVs, the amount of generated fragrance materials and remaining glycosides were analyzed with GC and HPLC. These results showed that most of GBVs could be metabolized gradually by skin microflora to release various fragrance materials. Further, in situ examinations were carried out. After applying the solution of each GBV on various regions of the body, such as scalp, foot and forearm, the generated fragrance materials were analyzed by using headspace technology. And we confirmed that GBVs, particularly β-D-glucoside derivatives, also gradually changed to fragrance materials on the skin. In conclusion, odorless GBVs possess an alternative effect of its unusual sustained-release deodorancy as deodorant ingredient on the skin. This approach, specifically studied for the deodorant ingredients, could be applied to improve the durability of the active ingredient for cosmetics.

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The combing response is one of the important quality factors of hair care products. In this report, an objective evaluation method for combing response was discussed, and a new type of evaluation device that is equipped with a vertical articulated type robot and a comb type probe mounted to a strain gauge was developed. It is applied to a hair tress with the view to substitute combing action of a human hand. The objects of the study are the factor analyses of the conditioner components for the combing response and application to the development of hair care products such as hair conditioners, the effects of cationic surface-active agents, the constituent hair conditioner were discussed and the evaluation results were compared with a sensory evaluation. The experimental results are summarized as follows: the effects of the combing response to the hair conditioners, based on several levels of concentration and varieties of cationic surface-active agents, were accurately detected, and a correlation to the sensory evaluated values was observed. From these data, this evaluation method was estimated to provide a rapid and objective detection of the combing response and is applicable for the development of hair care products. From the measurement of normal and damaged hair, a precise difference was detected and the method was found to be effective for the estimation of hair conditions.

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Demand for anti-aging cosmetics is increasing considerably. Until now, a great number of materials that are able to prevent human skin from aging (the anti-aging ingredients) have been sought by many researchers, however, few components were found to be useful in anti-aging cosmetics. Nowadays, the defensive functions in plants against oxidative stress from the outside have attracted considerable attention, therefore, we have aimed at applying new antioxidants in plants to the anti-aging cosmetic ingredients. Germinated sesame seeds were found to contain a strong natural antioxidant. As a result of purification and identification, it appeared that lignan glycosides were the main antioxidants in germinated sesame seeds, and we could succeed in discovering three new kinds of lignan glycosides. By evaluating the effectiveness of these compounds for anti-aging cosmetics, it was found that lignan glycosides showed scavenging activity on organic radicals, hydroxyl radical (ESR analysis), singlet oxygen, superoxide anion, and antioxidant activity against oxidation of squalene generated by UV irradiation and oxidation of linoleic acid induced by Fenton reaction. These results suggested that lignan glycosides in germinated sesame seeds were very useful as anti-aging cosmetic ingredients.

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Deterioration of applied makeup remains a serious concern for the busy modern woman, but little research has been published on this topic. Currently available “long-lasting” makeups do not perform satisfactorily, and a different approach is needed. Many forms of makeup film deterioration exist; our international survey of makeup users identified shiny spot formation following foundation application to be the problem most frequently complained of. Our goal was to identify those factors responsible for optical degradation and develop an effective means of countering this phenomenon. Our research confirmed that the secretion of sebum plays a key role in shiny spot formation. We studied the components of sebum causing optical degradation, and identified particular unsaturated free fatty acid (FA) as the main culprits. By lowering the melting point of sebum, unsaturated free FA caused wetting of the makeup substrate, altering its optical properties, leading to the formation of shiny spots. Understanding of the basic cause of optical degradation of the makeup film enabled us to design a new compound which can selectively adsorb specific FA. By chemically modifying the structure of certain clay minerals, we developed unique interlayered compounds having precisely controlled spacing of the silicate layers of the clay and selective adsorption properties. One compound we developed consists of zinc oxide precursor loaded in alumina pillar interlayered clay (ZA-pilc). In vitro and in vivo testing on powder foundations incorporating ZA-pilc proved that the compound was remarkably effective in suppressing optical degradation, prolonging the life time of makeup in actual usage conditions. Besides preventing optical degradation of makeup film, incorporation of ZA-pilc in cosmetic formulations may offer an additional benefit of reducing acne formation through selective adsorption of FA. Our experimental results indicate that ZA-pilc suppresses comedo formation in the ear of rabbits, suggesting the possibility of application in anti-acne preparations.

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Repeated exposures to sunlight cause sagging skin or deep wrinkles. These morphological changes, called photoaging, depend on the characteristics of dermal extracellular matrices (ECM), of which type I collagen is a major component. We studied cell growth and ECM formation of human skin fibroblasts under long-term UVA exposure, Secretion of type I procollagen was almost the same as that of the control, while cell growth and ECM formation were greatly inhibited. Reactive oxygen scavengers did not affect this inhibition. The effect of UVA was reproduced when the cells were cultured in UVA-irradiated medium, even though they were not exposed directly to UVA. The growth arrest was not seen when fresh fetal bovine serum was added to the UVA-irradiated medium. These results suggest that the inhibition of cell growth and ECM formation induced by long-term UVA exposure is due to denaturation of growth factors and/or chemokinetic factors rather than to direct cytotoxicity of reactive oxygen.

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Linoleic acid, one of the essential fatty acids, has a remarkable inhibitory effect on melanin synthesis by cultured melanoma cells. The activity of tyrosinase, an enzyme critical to melanin synthesis, was inhibited by linoleic acid but the level of tyrosinase mRNA was not affected, indicating that linoleic acid regulation of melanogenesis was due to post-transcriptional events. The inhibitory mechanism of linoleic acid was that it enhanced the proteolytic degradation of tyrosinase and led to a decrease in melanin production. In order to improve the stability of linoleic acid, liposomes were employed, which occurred skin permeation and resulted in a substantial amount of linoleic acid in the skin. Clinical trials with liposomal linoleic acid for skin hyperpigmentary disorders, such as melasma, showed hypopigmenting effects, suggesting that liposomal linoleic acid is useful as a skin lightening agent.

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It is well known that nail damages such as yellowing, split nails and peeled nails (onychoschisis) are caused by continuous use of nail enamel for a long period. Within serious nail damages, we aimed at split nails and peeled nails and basically investigated the relationship between fingernail moisture content and the mechanical properties of fingernails to make clear the factors affecting those nail damages. As a result, we newly developed the bending tester to evaluate split nail and peeled nail and established the method of evaluation of those nail damages. Moreover it is suggested that fingernails split easily under low fingernail moisture content and peel easily under high fingernail moisture content.

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“Sensitive skin” is an important problem in cosmetics research. Nowaday, there are still a few research studied in this field. To evaluate the sensitive skin, in self consciousness, we studied are as follows: 1) factors affecting on the conscious sensitive skin, 2) seasonal variation affecting on the skin sensitivity, 3) relationship between sensitivity of the skin and morphology of the stratum corneum obtained by tape-stripping method. As the results, it was suggested that 1) there are similar experience in the forming of the skin consciousness, 2) proportion of the conscious skin sensitivity is not changed within a year, but individuals are changed, 3) some of the stratum corneum parameters correlated to the skin consciousness, projected surface area of the corneocyte available for substantiate the skin sensitivity. Especially, the separation value of surface area which calculated from theoretical value is most useful in the parameters. Questionnaire and separation value of corneocyte's surface area are useful tools to evaluate the skin sensitivity.

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It was found that the foundation exposed to ultraviolet rays could accelerate the oxidization of squalene, a sebum component. This finding was based on the following experiment: 1) squalene and 2) squalene and foundation were applied individually on the human arm and exposed to sunlight for 1h. Then, the levels of oxidization of 1) and 2) were compared by the TBA method. The result of this experiment led us to the abovementioned finding. Thus the oxidization level of the squalene exposed to ultraviolet rays was examined with regard to each powder component of the foundation in order to determine the causative factors involved. As a result, titanium oxide was identified as one of the factors. Hence, the powder component which has the titanium oxide surface coated with silica was developed, thereby to make a prototype of foundation that will not allow the oxidization of squalene to be accelerated. The effect of this new foundation on the skin was compared with that of the conventional foundation using the back of a hairless mouse. The result verified that the newly developed foundation surpassed the conventional product in terms of mitigating the scale and induration in an epithelial change on hand, and inflammatory cell infiltration in a dermal change on the other hand. This suggests that inhibiting the accelerated oxidization cased by the foundation exposed to ultraviolet rays can help mitigate their adverse effect on the skin as well.

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