perming

A perm, short for permanent wave, is a chemical hair treatment that reshapes curly or wavy patterns by breaking and re-forming the disulfide bonds within the hair cortex. The result is a lasting curl or wave that remains until new hair grows out or it is altered by further chemical processing.

Typical operation involves washing and towel-drying the hair, then wrapping damp strands around rods or rollers to determine the intended curl pattern. A waving solution containing a reducing agent is applied to soften the bonds, and the hair is left to process for a set time. The rods are then rinsed and a neutralizer is applied to oxidize and re-form the bonds in the new configuration. After a final rinse, the hair is styled as usual.

Chemistry and hair health are central to results. The reducing agents are commonly thioglycolates, such as ammonium thioglycolate, and the neutralizer is an oxidizer (often hydrogen peroxide) that rebuilds the bonds. Outcomes depend on hair type, condition, porosity, and the size of the rods used. Overprocessing or using incompatible products can lead to damage, frizz, or uneven curls.

Variants of perms include alkaline (cold wave) perms, which tend to produce stronger curls and work relatively quickly, and acid perms, which are gentler on the hair but may require longer processing. Exothermic perms generate heat during processing, and digital or rod-based methods use heated or specialized rods to create looser waves or specific textures.

Aftercare is important: minimize washing for 24–48 hours, use moisture- and sulfate-free products, and limit heat styling while the hair is recovering. Regular conditioning helps maintain curl integrity.