Hairstyles, Hair Care & Fashion

Perms and a Burnt Smell

Q: Is an acid perm or an alkaline perm more likely to smell burnt after processing? Are there certain perms that would cause the burnt smell a few days after a perm or is it the fact the perm may not have been rinsed properly?
A: Typically, an alkaline perm formula has a much stronger and more unpleasant odor than that of the acid perm. This is because of the use of ammonia (in ammonium thioglycolate) used to break the chemical bonds within the hair that allow the wave pattern to be reconfigured as you desire it to be. Most people seem to identify this odor as that of either rotting eggs or burnt hair. The burnt hair comparison is somewhat appropriate as part of the processing involves a chemical reaction within the hair that gives off its own heat as a by-product.
Acid perms use no ammonia, and instead are formulated with glyceryl monothioglycylate which doesn't produce its own heat, and has to be exposed to heat from an outside source (typically an hood dryer). It is a gentler formula but also produces curls that are not as firm (and in some cases not as long-lasting) as alkaline perms.
Unfortunately, it seems that the odor of an alkaline perm is present, regardless of how well it is rinsed afterward. The intensity of the odor also varies from manufacturer to manufacturer. However, it can be said that making sure to leave the neutralizing solution on the hair the proper length of time IS key to minimizing the odor of any perm.
If, however, your hair still has an odor after perming, neutralizing and rinsing the hair thoroughly, here's a handy at-home tip to help:
Take one cup of white vinegar and two cups of water and combine them. Use this on as a rinse after shampooing your hair. Allow the solution to remain on the hair. Blot the hair and scalp dry with a clean, soft towel, and then allow the hair to dry naturally, or use a hair dryer with low heat and a diffuser attachment on the airflow nozzle. The acid in the vinegar will not only help to cut through the odor, but will also help to contract the cuticle layer and leave the hair shinier.
If you want even more conditioning impact, combine 1/2 cup of white vinegar with a cup of your favorite conditioner and apply it as normal after shampooing. It will help remove the odor, seal the cuticle and keep the hair super-hydrated.
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Smell after a perm that doesn't go away
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