Comparative Study for Hair Protection Effect of Hair Essence Prepared Using Human Hair Keratin

This study evaluated the protective effects of keratin essence on hair subjected to physicochemical damage. Hair from a woman in her early thirties, who had undergone multiple dyeing and digital permanent treatments, was used. The study divided the hair into four groups: control, damaged, basic essence-treated, and keratin essence-treated. Results showed that keratin essence improved hair protection by reforming and filling gaps between cuticle scales, as observed through scanning electron microscopy. The keratin essence-treated hair exhibited lower brightness and yellowish-blue color but higher reddish-blue color compared to other groups, indicating improved coloring efficiency and structural protection against damage from dyeing treatments.