What happens during the neutralization step in a perm?

• A. It neutralizes the solution pH to stop processing.
• B. It adds moisture to the hair.
• C. It heats the curl to set.
• D. It rebuilds disulfide bonds to set the new curl pattern and restore hair strength.

Answer: (D)

Neutralization in a perm oxidizes the reduced hair and re-forms the disulfide bonds, which locks in the new curl pattern and restores hair strength. After the reducing step breaks those bonds to loosen the hair, the neutralizer rebuilds the bonds that hold the shape, stabilizing the curl and helping the hair regain its strength. It also helps stop further processing by restoring normal conditions, but its primary role is re-linking the keratin chains. It doesn’t add moisture or actively heat the hair to set.