| 摘要 |
Provisions are made so that an SPF value having high correlation with an in vivo SPF value can be calculated in vitro using a common calculation equation regardless of the material type used. Transmitted UV intensities I( lambda ) are corrected by respective erythemal effectiveness coefficients EE( lambda ) to calculate an erythema-inducing UV intensity EUI, and the elements of I( lambda ) from lambda =320 to 400 nm are summed to calculate a transmitted UV-A intensity; then, from the ratio UV-A/EUI, a theoretical value alpha TH is calculated for the base alpha of a photoaugmentative effectiveness alpha UVA, and using EUIx alpha THUVA, an ultimate theoretical value EUIUL of EUI is calculated. When EUIUL is larger than 75, the SPF value is calculated from 1350/EUIUL; otherwise, the SPF value is calculated using an empirical equation. |
