Thermal Induced Changes in Cuticle and Cortex of Chemically Treated Hair

The study examines the effects of thermal and chemical treatments on hair, focusing on structural changes in the cuticle and cortex. Techniques like x-ray scattering and electron microscopy reveal that treatments such as bleaching and acid straightening, especially when combined with heat, cause significant damage, including melanin degradation, cuticle detachment, and breakdown of structural components like 18-MEA and disulfide bonds. These changes result in increased fragility, porosity, and irreversible damage, affecting hair's mechanical properties and appearance. The research underscores the need for safer cosmetic formulations and further investigation into these treatments' effects.