Hair Color
Manufacturers create an array of colors and lighteners that give the stylist the ability to create subtle to
dramatic hair color changes. Haircolor products fall into the following general categories:
· Nonoxidative
Color
· Oxidative
Color
· Lighteners
· Developers
· Vegetable, Metallic and
Compound Dyes
Nonoxidative Colors
1.
Temporary Colors
are non-reactive, direct dyes that only coat the surface of the hair
shaft. There's nothing to lighten the hair and no chemical changes occur in the solution.
These colors are called certified colors and are accepted by the government for use in foods,
drugs and cosmetics. Temporary colors last only until they are shampooed out.
2.
Semi-permanent colors
last through several shampoos, then the color molecules gen-
erally shampoo out. Semi-permanent colors are dye molecules in a solution that are able to
penetrate the cuticle layer of the hair versus coating the hair shaft as with temporary colors.
Semi-permanent color molecules are smaller in size and weight than the molecules found in
temporary color products, and they are slightly alkaline in pH.
Semi-permanent colors use a
direct dye process, which means the color is present without the need to chemically develop it. Direct
dye colors need no mixing and the color you see in the bottle is the color that is deposited on the hair.
Oxidative Colors
1.
Long lasting semi-permanent colors
(sometimes referred to as demi-permanent or
oxidative without ammonia) use a low volume peroxide to develop the color molecules and aid
in the color depositing. Ammonia is a colorless gas with a strong odor, composed of hydrogen
and nitrogen.
Peroxide alone does not lift color from the hair. It needs an alkaline substance such as
ammonia to lift color. Therefore, long lasting semi-permanent or demi-permanent colors are only able
to add color to the hair. They cannot subtract, lift or lighten. Long lasting semi-permanent colors are
available in liquid, cream and gel forms.
2.
Permanent hair colors
(sometimes referred to as oxidative with ammonia) use an oxi-
dation system that starts out with colorless molecules. When these molecules are combined
with peroxide, a chemical reaction (change) occurs, building colored molecules. The small
molecules enter the hair with the aid of an alkaline substance such as ammonia and then, as
they oxidize in the cuticle and the cortex, they link together to form a permanent colored mol-
ecule.
When this happens, they are permanently anchored in the hair. It is the combination of the
ammonia and hydrogen peroxide that is also responsible for the permanent color's ability to both lighten
the hair's natural color and deposit artificial color.
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CHEMISTRY
Oxidants (often called developers) are products that have the ability to
release oxygen, which is needed for a chemical change. Oxidative
colors are mixed with an oxidant (developer) such as hydrogen peroxide.
Nonoxidative colors are not mixed with oxidants and are used straight
from the bottle. In the oxidation process a substance loses an electron
and oxygen is acquired. When a substance gains an electron and
oxygen is released the process is called reduction. This process not only
occurs in hair color services, but in perming/relaxing services as well.
