Time-of-flight secondary ion mass spectrometry (ToF-SIMS) analysis of the application of a cationic conditioner to "clean" hair.

In this study the applicability of the surface-sensitive ToF-SIMS technique to hair analysis and associated aqueous processing is evaluated. ToF-SIMS analysis of "as received" human hair indicates the presence of silicones, anionic surfactants, and cationic conditioners, from previous treatments, on the fiber surface. Cleaning of the hair with SLS or SLES results in adsorption of the surfactants onto the fiber surface. In particular, the more non-polar surfactant components have greater substantivity for the fiber surface, as indicated by the relative increase in their ToF-SIMS intensity. Application of the Incroquat Behenyl 18-MEA conditioner to both "virgin" and bleached hair results in the adsorption of the cationic C18, C20, C22, and C21 surfactant components onto the hair surface. The ToF-SIMS data indicate higher levels of conditioner on the bleached hair relative to the undamaged hair.