The evaluation method of the effect of UVA protection of sun-proof cosmetics

These UVA effects may be direct damage or effects on the skin immune system,yet there is no uniformly accepted method for the evaluation of sunscreen UVA protection.This paper introducts in-vivo and in-vitro method for the evaluation of sunscreen products of UVA protective.Using MX16 Melamein-Erythema-Index-Meter to measure a photochemical reaction occurring in human skin seen as grey/brown skin coloration in response to relatively high doses of UVA readiation.This coloration,called Immediate Pigment Darkening Dose(IPD).In-vitro method for UVA protection through it was measured the ultraviolet absorption by a broad spectrum 320nm～400 nm UV detector.This shows a good correlation with In-vivo method.The in-vitro method is simple,rapid and reproducible.It can be used instead of the in-vivo method.