What happens to the pH of hair when undergoing a relaxer treatment?

When hair undergoes a relaxer treatment, the pH of the hair raises significantly. Relaxers typically contain alkaline substances, which increase the pH level considerably, often making it more basic. This elevated pH is crucial because it allows the cuticle of the hair to swell and lift, which is necessary for the relaxer to penetrate the hair shaft and break down the disulfide bonds within the hair structure.

As these bonds break, the hair can be straightened and reshaped. After the treatment, it's essential to balance the hair back to a more neutral pH to restore its integrity and health, usually achieved through the use of a neutralizing shampoo. Understanding this pH shift is vital for cosmetologists to maintain hair health and achieve the desired effects of chemical relaxers safely.