In what way do alkaline perms differ from acid perms?

Alkaline perms are characterized by having a higher pH compared to acid perms, which allows them to be more effective on resistant hair and produce a firmer curl. The higher pH results in a stronger solution that opens the hair cuticle more effectively, allowing the waving solution to penetrate the hair shaft efficiently. This strength makes alkaline perms suitable for certain hair types, particularly those that are coarse or resistant.

In contrast, acid perms typically have a lower pH, making them milder and better suited for finer or damaged hair. The chemical processes and end results differ significantly based on this pH level, impacting the firmness of the curl and the overall condition of the hair post-treatment. Understanding these differences is crucial for selecting the appropriate perm type based on the individual needs of the hair.