Perm French Braids
A: The quick answers are "Yes you can use perm solution on hair that is in a French Braid" and "Yes, you should leave it on the same amount of time to process." The processing time depends on the texture and condition of the hair, not the shape of the configuration you are trying to put the hair in.
The reason is that in order to reshape the wave pattern of the hair, you need uniform tension and configuration on the hair at all points along its length.
A French braid however, has varying levels of tension in the hair, and no uniformity in the shape the hair is placed in. At the scalp, the hair may be too taut in places and therefore subject to breakage and damage when the perm solution (and subsequently, the neutralizer) is applied. Toward the middle and ends, the tension will likely be insignificant and result in no visible results.
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See also:
Perms and perming hair
The scientific processes during perming & relaxing
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