Effects of Cosmetic Emulsions on the Surface Properties of Mongolian Hair

Abstract

In the light of clean beauty and sustainability requirements emerging in the personal care market, the urgent need for the replacement of silicones in hair conditioners—with comparable performance and customer experience—has been highlighted in the industry. In this context, the goal of the present study was to investigate the physical effects of different silicone-free conditioner formulations on Mongolian hair after damage due to bleaching and compare the results to property changes induced by a classical silicone-containing formulation. To that end, the morphology, structure, and composition of strands and individual fibers of this hair type were characterized before and after bleaching by means of optical microscopy, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). It is shown that oxidative bleaching causes significant damage to the native hair surface, leading to local depletion or even large-area removal of the outer hydrophobic lipid layer. This results in enhanced wettability of the bleached hair by water (as confirmed by contact angle measurements) and is accompanied by an undesired loss of hair gloss and softness. Upon treatment with suitable cosmetic emulsions, the natural hydrophobicity of intact Mongolian hair can be partially or fully restored, with silicone-free formulations having effects similar to those of established silicone-containing products. The successive influence of bleaching and conditioning was further monitored using inverse gas chromatography (iGC), a technique that probes changes in surface energetics and polarity over an ensemble of an entire hair strand through interactions with specific molecules at the solid/gas interface. The resulting data mirror the macroscopic behavior of the bleached/conditioned hair and provide a quantitative scale for measuring damage and repair effects. Most notably, the effect of bleaching and subsequent conditioning on the haptic perception of hair strands could also be quantified with the aid of a biomimetic measurement system, which identifies increased friction (both tactile and sliding) as the major cause for the strawy feel of bleached hair and indicates successful relubrication after treatment with suitable conditioner formulations. Finally, the different physical properties determined for native, bleached, and reconditioned Mongolian hair are found to be reflected in application-oriented tests, namely in vitro measurements of wet and dry combing work. Overall, the data collected in this work shed novel light on the surface properties of Mongolian hair and highlight that effective hair conditioning after damage can be achieved without silicones in advanced cosmetic emulsions based on octyldodecyl myristate and glyceryl oleate.

The Role of Burdock and Black Radish Powders Obtained by Low-Temperature Drying in Emulsion-Type Hair Conditioners

“…In recent years, a trend has emerged to eliminate silicones from cosmetic formulations, including hair conditioners. For example, Liu [21] studied the effects of various siliconefree conditioners on Mongolian hair damaged by bleaching and compared the results of physicochemical tests with the changes in properties achieved after using a classic siliconecontaining formulation. It was found that effective conditioning of damaged hair could be achieved without silicones in advanced cosmetic emulsions based on ingredients such as octyldodecyl myristate or glycerol oleate.…”

Analysis of the hydration water on the surface of human hair using a combination of infrared absorption vibrational spectroscopy and multivariate curve resolution

“…5 This adsorbed water has a significant impact on the smoothness, appearance, and maintenance of hairstyles. 6,7 The wettability of hair is directly connected with the physicochemical properties of its surfaces. 8 Accordingly, it has been reported that treatments of hair with chemicals, such as bleaching, permanent waving, and conditioner, have significantly affected its wettability as compared to chemically untreated hair.…”

“…The physical properties of hair change considerably depending on the water retained inside or adsorbed on it 5 . This adsorbed water has a significant impact on the smoothness, appearance, and maintenance of hairstyles 6,7 …”

Comparison on Quality Performance of Human Hair Types with Herbal Oils (Grape Seed/Safflower Seed/Rosehip) by Analysis Techniques

“…It was concluded that the application of antioxidants based on procyanidins-derived seeds could protect hair against reactive oxygen species . The studies in the literature showed that various seed oil types could be evaluated in many industries such as cosmetics, pharmaceutical, and agro industries. − The literature also showed that safflower, rosehip, and grape seed oils were utilized as agents inducing hair growth to improve the wave effect, to decrease the damage to the hair, to accelerate hair regeneration, and to promote hair follicle cells. − …”