A collaborative research group between Professor Shigeki Nakauchi of Toyohashi University of Technology, Department of Information and Intelligent Engineering, and Kao Corporation Skin Care Research Institute has newly evaluated the UV protection effect easily and quantitatively by analyzing images using UV rays. Succeeded in developing a new method.
Currently, the UV protection effect of sunscreen agents is calculated according to the measurement method established by ISO (International Organization for Standardization), but the effect may be reduced by the effects of sweat and friction after applying sunscreen agents. ..For this reason, it has been considered necessary to measure the UV protection effect in actual use situations.
Therefore, in this research, we have developed a UV spectroscopic image measurement technology as a new evaluation method for UV protection.This technique is a method of determining how much ultraviolet rays can be absorbed by the sunscreen coating film by detecting the ultraviolet rays reflected from the sunscreen coating film.
When the change in the UV protection effect due to the application of the sunscreen agent was actually investigated using this evaluation method, it was found that the UV protection effect decreased with the passage of activity time, and the decrease was not uniform.It is considered that this is because the coating film of the sunscreen agent changed over time and partially due to the activity.Furthermore, when the sustainability of the UV protection effect was examined in various usage scenes, it was observed that the UV protection effect was significantly reduced even with friction that leaned against the chair.Therefore, it was shown that durability against friction is very important for sustaining the effect of the sunscreen agent.
