Discovery of a sol–gel reinforcing the strength of hair structure: mechanisms of action and macroscopic effects on the hair

Abstract

The human hair presents a fibrillar structure, composed of keratinized cells, covered by a wall of cellular scales, piled up like tiles on a roof. Substantial variations in diameter exist in the population. Fine hair is a major concern for women and men. Hair may lack volume and lack of firmness and bounce. Hairstyles lack volume and hold, and hair is flat and difficult to style. To strengthen the hair structure, penetration of materials, like polymers, could be a realistic approach. The hair cuticle barrier, however, prevents big molecules to penetrate. To overcome this hurdle, reactive sol–gel have been studied, leading to the identification of the 3-aminopropyltriethoxysilane. Smaller than polymers, this silane has been studied on the key question of the penetration. After having understood its potential in penetration, the effect on mechanical transformation has been studied. The objective of this work was also to evaluate the efficacy of the 3-aminopropyltriethoxysilane, formulated in products for fine hair to respond to the needs of both feminine or masculine head hair. Several studies and techniques were used to determine the impact of the optimal efficacy of 3-aminopropyltriethoxysilane by provisory transforming hair fiber. To improve hair resistance, reactive sol–gels have been studied, leading to the identification of the 3-aminopropyltriethoxysilane. After treatment, material is detected inside the fiber. The resistance of material to shampoos leads to think that the molecules reacted to oligomers. Several studies and techniques were used to determine the impact of the optimal efficacy of 3-aminopropyltriethoxysilane. The three-point bending measurements showed that 3-aminopropyltriethoxysilane improves the mechanical resistance of dry hair. In addition, the morphology of the surface revealed an absence of a perceptible coating. These results explain the effect of body given to fine hair, and its remarkable natural touch. Other experiments have been done to elucidate the intimate effect of material on the complex structure of hair.