A skin care product is valued for not only its effect on the skin but also its positive effects on psychological wellbeing. Examples of such effects are moisturization and relaxation. A skin care product produces psychological effects by stimulating the somatosensory system. Signals received by receptors in the skin influence the activity of the autonomic nervous system, endocrine system and immune system and various emotions are thus evoked. A positive feedback loop is produced by the application of a skin care product: use evokes positive psychological and skin care effects and, in turn, each enhances the effects of the other. This paper discusses the relationship between using a skin care product and the psychological effects of its use from the perspectives of somatosensory function, emotional response and skin care effects.

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Parts of the face where more sebum is secreted are conventionally called Zone T. However, these sites are not always areas where makeup is apt to come off. To verify this idea, we conducted a survey on the feelings of the beauty staff, took sebum measurements from several locations on the face, and observed sebum secretion. The results confirmed that sebum secretion in the individual could be ranked by dividing the face into 19 parts. As a next step, we evaluated the effects of a milky lotion on makeup and its staying power on these parts. Findings indicated that the application of foundation was affected by the sebum secretion of each individual part; thus, makeup fading differed according to location and amount of sebum secretion. Based on these results, we suggest that the nose, the brow, the inward upper cheeks, and the jaws be called Zone I because more sebum is secreted in these places. We also propose that moisture products for base makeup be suitably selected and properly used according to the nature of the skin of each person.

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Commercial makeup can enhance beauty when used on youthful skin. But when the same makeup is applied to aged skin, the result is often artificial and unnatural-looking. To find the cause of this phenomenon, we investigated the optical properties of skin and discovered that they strongly correlate with microtopography of the dermal surface. We learned that lateral diffusion of light on the skin surface is a key contributor to its optical qualities, and that this diffusion is strongly influenced by the condition of the microtopography. Further studies resulted in the discovery of an important optical parameter which we termed “Lateral Diffusion Index” (LDI). Youthful skin, with its more distinct and uniform pattern of microrelief, was found to possess a higher LDI value than does aged skin, with its flatter and more irregular pattern of microrelief. We then confirmed the practical application of our discovery by incorporating specially designed powdered fiber (300μm nylon fiber) into an experimental makeup to optimize light diffusion characteristics and substantially increase the LDI value of aged skin. Comparison studies demonstrated this new makeup to be more effective than traditional makeup in making aged skin appear more naturally alive and vibrant.

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When you evaluate the appearance of the skin, which part of the face do you pay attention to? The purpose of the present study is to identify the most important part of the face in skin care routines as well as in the use of cosmetics to enhance skin's beauty. A sensory evaluation of 14 attributes of a model's skin, such as ‘rough texture, ’ ‘luster, ’ and ‘smoothness, ’ in addition to ‘skin beauty’ as an overall assessment of the skin, was conducted. At the same time, the eye movements of the evaluators was recorded with an eye movement measuring system. The main findings were as follows. For many attributes the evaluators fixated mainly on the cheek region. The nose was also often fixated on, e.g., in the evaluation of prominent pores the fixation concentrated on the nose on and wings of the nose. These parts fixated on corresponded well with the parts where the evaluators reported that they looked. When subjects were asked to assess luster, fixations tended to be concentrated on the tip of the nose and the cheeks. The part fixated on differed depending on the attributes evaluated. In the evaluation of skin beauty, the fixations were distributed over a wider region, including the upper cheek, the area around the nose, the area around the mouth, and the lower cheek. In conclusion, eye movement during sensory evaluation was elucidated objectively. These findings are not only important for developing skin care and make-up techniques, but also for determining appropriate measurement areas in skin bioengineering techniques.

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Properties of the perfluoroalkylethyl acrylate (FA)/2-hydroxyethyl methacrylate copolymers and their applications for cosmetics was studied. The main conclusions from this study can be summarized as follows: This copolymer made it possible to repel oil both in air and in water. Its behavior was investigated by surface chemistry-based measurement (contact angle, ESCA) used with flat substrate (Al plate). This technique will be applied to prepare cosmetics which are durable against sebum in all environments.

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