In which hair care service is glycerl monothioglycolate used?

Glycerl monothioglycolate is a key ingredient commonly used in perming solutions. It acts as a reducing agent that helps to break down the disulfide bonds in the hair's keratin structure. This allows for the reshaping of the hair during the perming process, enabling curls or waves to be formed and set in place.

The role of glycerl monothioglycolate specifically in perms distinguishes it from other hair care services. For example, relaxing treatments often utilize different chemical agents aimed at straightening hair rather than creating curls. Color treatments encompass dyes and bleaches focused on altering the hair's hue, rather than restructuring it. Deep conditioning is primarily concerned with restoring moisture and health to the hair without altering its shape or texture through chemical means. Thus, the use of glycerl monothioglycolate is uniquely suited to the perm service, making it the correct choice for this question.