Colorful Pigments Based on Multicomponent Metal‐Phenol Network Nanoparticles for Hair Dyeing

Abstract In this study, we developed a complex polyphenol‐metal ion system, in which two polyphenols represented by gallic acid (GA) and tannic acid (TA) chelated with metal ions leading to the formation of pigments composed of metal‐phenol networks (MPN). The doping of GA and TA creates a mutual synergistic effect, which makes it chelate with metal ions to produce a more complex structure of MPN, and finally obtain more colorful MPN pigments. The MPN pigments can be easily deposited on the hair surface through covalent and non‐covalent interactions, resulting in a series of hair dyeing effects with high color saturation and excellent stability. With many advantages such as low raw material cost, short hair dyeing time, simple process, good biocompatibility, less fading, and antioxidant, this composite polyphenol‐metal ion material offers the possibility to replace the classical irritant hair dyes commonly used in existing cosmetics.