Abstract
Many methods of in vitro SPF evaluation have been developed in order to measure SPF of sunscreen products. In this study, we compared two spectrophotometric in vitro measurements using the skin cast made of Luviset CAP- $X^{R}$ resin and Transpor $e^{R}$ tape as substrate with two in vivo measurements using guinea pig and human. And we also observed the radiation reaching on the earth's surface in Seoul for one year and the change of the primary skin irritancy along the change of SPF value. According to the our research, the first, in vivo measurement using guinea pig had the close agreement with SPF measurement using human and showed the tendancy that guinea pig SPF was lower than human SPF. The second, there was the good relationship between in vitro SPF by using Transpor $e^{R}$ tape and in vivo SPF, and it is possible to predict human SPF from Protection Index(PI) by using tape. The third, it is thought that SPE 20 is reasonable value because of UV intensity in Seoul and the primary skin irritancy of higher SPF than 25. So we propose that it is important to distinguish the sunscreen product having higher than approximate 25 from the category of general cosmetics including lower SPF sunscreen product.oduct.
