Iron Gall Ink Revisited: A Surfactant-Free Emulsion Technology for Black Hair-Dyeing Formulation

Sang Yeong Han,Eunhye K Kang,Insung S Choi

doi:10.3390/cosmetics8010009

Abstract

Inspired by the redox reactions in the preparation of the iron gall ink that has been used in Europe since the Middle Ages, we developed a technology for forming the oil-in-water emulsions, without any surfactants and emulsifiers, by homogenizing a mixture of tannic acid, gallic acid, Fe(D-gluconate)2, and natural oil, which are all approved as cosmetic ingredients. Various plant-derived oils, such as argan oil, olive oil, sunflower oil, grape seed oil, hemp seed oil, peppermint oil, rosemary oil, and ylang-ylang oil, were used as an oil phase for the emulsion formation, and all the fabricated emulsions exhibited the capability of black hair-dyeing. This surfactant-free emulsion technology for combining the hair-dyeing capability of Fe3+–tannin complex with the hair-fortifying property of natural oil would have great impact on the hair-cosmetic industry.

Highlights

In this work, considering that the surfactants would be potentially irritable to the hair, scalp, and skin, we investigated a surfactantfree, oil-in-water emulsion technology for black hair-dyeing formulation, in which the Gallic acid (3,4,5‐trihydroxybenzoic acid, ≥97.5%, Merck), tannic a iron(II) gluconate dihydrate (Fe(D‐gluconate)2∙‧2H2O, ≥98%, Merck), and N
(1) It does not require any surfactants emulsion-stabilizing chemicals for the emulsion haircare applications: (1) It does notorrequire any surfactants or emulsion‐stabilizing formation, which are potentially irritable to the hair and skin, as well as the unwanted chemicals for the emulsion formation, which are potentially irritable to the hair and skin, components in the formula to the customers in some countries
(2) The emulsion is stable at the pH values of the skin and not harmful or color of the Fe3+ –tannin complex is innately dark purplish black, which would be useful irritable to the scalp and skin

Summary

Introduction

In this work, considering that the surfactants would be potentially irritable to the hair, scalp, and skin, we investigated a surfactantfree, oil-in-water emulsion technology for black hair-dyeing formulation, in which the Gallic acid (3,4,5‐trihydroxybenzoic acid, ≥97.5%, Merck), tannic a iron(II) gluconate dihydrate (Fe(D‐gluconate)2∙‧2H2O, ≥98%, Merck), and N Ink the blackening is achieved the air oxidation of Feas to we recently use of the Fe2+by–tannin complex a Fe reaction ions in the Fe2+ –tannin complex that is prepared by mixing tannins (e.g., gallic acid and interfacial‐film formation [32], protein sequestering [33], black hair‐dyei tannic acid) from oak galls and green vitriol (iron(II) sulfate, FeSO4 ) [30,31].

Results

Conclusion