Page 16 - Understanding light, colour and hair colour_Neat

VISIBLE LIGHT AND HOW WE SEE HAIR COLOUR:

Visible light is absorbed by the human hair, the colours of its pigments are
reflected. This reflection is recognised by the red blue and green Retina

cone cells.

By removing the human hairs natural pigments the hair will reflect and be
recognised as white by the Retina cone cells in human eye.

It is also possible to remove all the human hairs natural pigments and
replace them with artificial pigments from a permanent hair dye. The

reflection from the artificial pigment is changed, and the human hair colour

is now recognised as a different colour by the red green and blue cone cells

in the Retina.

SO HOW DOES HAIR DYE WORK?

Once the chosen hair dye is in the mixing bowl it does not become active

until it is mixed with hydrogen peroxide, a reaction occurs from the

Ammonia in the hair dye when applied to the hair, causing the cuticle
scales to rise up allowing the hair dye molecules to enter the hair shaft.

Once the hair dye molecules have entered the internal hair shaft they begin

to expand and join together dying everything in their path.

(Please see Fig. 15)