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CHEMISTRY
· Rinsing removes the processing lotion.
· A second chemical, the neutralizer (also called rebonding lotion), reforms
the disulfide bonds into the new configuration. The resulting chemical
change in the hair holds the hair in its new position.
Perms fall into two primary categories:
1. Alkaline waves (cold waves), which are processed without heat and
have a pH of approximately 8.0-9.5.
2. Acid waves (heat waves), which are processed with heat and must
be wrapped with tension. Acid waves have an approximate pH of
6.9 to 7.2.
The main chemical ingredient found in alkaline waves is thioglycolic acid
or its derivatives and ammonium hydroxide. Ammonium hydroxide is
added to the formula to shorten the processing time.
It is also responsible
for the swelling that occurs during this process, which makes it easier for the
thioglycolic acid to penetrate the hair structure and break the disulfide bonds.
Processing begins as soon as the chemical has been applied to the hair.
The main chemical ingredient found in acid waves is glyceryl monothioglyco-
late. In acid waving, speed is sacrificed for a more controlled curl and less
damage to the hair when procedures are carefully followed. Heat is sometimes
used to assist in the penetration of the hair structure.
The main ingredient found in most neutralizers (or bonding lotions) is either hydrogen per-
oxide, sodium perborate, or sodium bromate.
All three of these ingredients can cause additional
damage to the hair if left on longer than specified by the manufacturer.
Relaxers
Just as a perm adds curl and body to hair by changing its molecular structure, a chemical relaxer
reduces curl in excessively curly or wavy hair by changing its molecular structure.
· The reforming (relaxing) product, which is usually formulated in a heavy cream base, is
applied to the hair and holds the hair in a straight position while it is being processed. In
addition a smoothing or pressing action is applied to the softened hair, causing the entire
protein structure to relax to the straighter position.
· The neutralizing (bonding) step utilizes a neutralizing shampoo or lotion to reduce the
swelling caused by alkaline formulas. This chemical change causes the hair to be held in the
new straight configuration.
Shifting and
breaking of
disulfide bonds
Disulfide bonds
reformed
