Mechanism of hair bleaching: an EPR study

Hair bleaching is a vital part of hair care industry. Unfortunately, the bleaches are strong oxidizing reagents, and apart from lightening the hair colour, cause some damage to the hair. The most successful recipes for hair bleaching work quite selectively, by causing minimum damage while providing the required lightening effect. However these recipes have been largely developed by the trial and error method, and the chemistry involved in the hair bleaching reactions is not well understood. The bleaching is likely to proceed via formation of free radical intermediates. This proposal aims to use EPR spectroscopy to unravel the mechanisms involved in hair bleaching and identify the main intermediates. Such mechanistic understanding of the chemistry involved in hair bleaching will help develop more selective, less damaging recipes in the future.