Page 56 - HAIR COLOUR

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
ammoniums 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 (Fig 54.)

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