Page 25 - HAIR COLOUR

Chapter 3

Reforming the Human Hair Permanently and Semi-Permanently

It is possible to reform your hair temporarily by using water and drying
with heat, and permanently by the use of chemicals as follows.

Reforming the curl pattern of a human hair takes place in the internal
protein structure beneath the layers of cuticle scales in the cortical cells.

It is believed that the internal protein structure is made up of Polypeptide
Chains; the links in these chains are what hold the hair in its original
formation. There are three main links that hold the Polypeptide Chains
together and they are called Bonds:

1. Salt Bonds.
2. Hydrogen Bonds.
3. Disulphide Bonds.

Both Salt and Hydrogen Bonds can easily be broken down with plain
water. It is believed that the Salt and Hydrogen Bonds are the Bonds that
are dissolved by water during the Shampoo and Set procedure. The hair
is shampooed the salt and hydrogen bonds are dissolved; the hair is now
reformed by either combing waves, wrapping around rollers, or shaping
in pin curls. The hair is now placed under a hood dryer and as the water
dries out of the hair, new salt and hydrogen bonds are formed holding the
hair in its new formation.

The reason the curl is not permanent is that; humidity is such a small

molecule that it passes right through the hair. The human hair is capable
of absorbing 90% of its own body weight in water from the humidity that
passes through it. Once more this new water breaks down the new salt
and hydrogen bonds allowing the unbroken disulphide bonds to return the
hair to its original formation. This makes it understandable why the same
shampoo and set would only last minutes in a Malaysian jungle, but for a
whole week in London.

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