California Cosmetology Written ExamChemical Texture ServicesMedium
During a permanent wave service, a cosmetologist applies neutralizer after processing and rinsing. What is the primary chemical function of the neutralizer at this stage?
- AIt softens the hair further to allow the curl to relax slightly
- BIt breaks additional disulfide bonds to enhance curl definition
- CIt re-forms disulfide bonds through oxidation, hardening the hair in its new curl shape
- DIt lowers the hair's pH to below 4.0 to strip remaining protein
Show answer & explanationAnswer & explanation
Correct answer: C. It re-forms disulfide bonds through oxidation, hardening the hair in its new curl shape
Neutralizer, typically hydrogen peroxide, is an oxidizing agent that stops the action of the reducing lotion and rebuilds (re-forms) the broken disulfide bonds in their new curved configuration, hardening the hair into the new curl pattern.
Why the other options are wrong
- A. Neutralizer hardens hair into shape rather than softening it further.
- B. The reducing lotion breaks bonds during processing; neutralizer rebuilds them.
- D. Neutralizer's job is oxidation of bonds, not protein stripping via extreme pH.
Neutralization (Oxidation)
The final step of a perm where an oxidizing neutralizer (usually hydrogen peroxide) re-forms disulfide bonds, hardening hair into its new curl shape.
- Neutralizer = oxidizing agent, typically H2O2
- Stops reducing action and rebuilds disulfide bonds
- Rinse thoroughly before applying to remove excess reducing lotion
Memory trick: Reduction breaks, oxidation makes—neutralizer is the glue that locks in the new curl.