Correlation Between Sun Protection Factor and Hair Color Difference Index in a New Method for Evaluating Sunscreens' Ultraviolet Protection Efficacy in Hair: An Experimental Study.

ABSTRACT:

Background

This study aimed to establish a novel method for evaluating ultraviolet (UV) protection efficacy on hair, focusing on the relationship between sun protection factor (SPF) and UV-induced hair color changes. We propose a hair SPF (HSPF) that measures the extent of hair color change following UV irradiation.

Materials and methods

In in vitro tests, we used UV standard samples with known SPF values (P2, P5, and P8) to construct a standard curve according to hair color changes before and after UV irradiation. Hair samples were analyzed using the CIELAB color space system, calculating the ΔE value to represent the color difference. To assess the UV protection properties of various hair care formulations (oils, essences, and balms), we compared their HSPF with the standa

SUBMITTER: Oh JH 

PROVIDER: S-EPMC12712344 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature