Abstract
An investigation of consumer's opinion about the foundation was conducted to 1600 Japanese females. We also carried out the examination of the facial skin conditions on 125 healthy Japanese females objectively and asked same questionnaire.
From the analysis of the questionnaire, people are more conscious about “oilyness”, “coming off”, “shining”, and so on which are related with sebum in general. Therefore, two evaluation methods in vivo for the deterioration of foundation were developed. Two evaluations were performed by measuring 1) the reflective light, and 2) amount of removed foundation from the face. The relationship between sebum and these evaluated values from two experiments clearly investigated that the deterioration of foundation was caused by sebum.
According to our investigations, we concluded that the main reason of the wear-off during the foundation application is sebum.
