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HHHHair CCCColouring

Hair Colouring is the process of adding

colour to the natural hair colour. It is used to

disguise or cover over white hair, or to

enhance and change the natural hair colour.

Hair Colouring

The natural pigments of hair are found in the

cortex; outermost layer of the hair-shaft- the

cuticle-that covers and protects the cortex, is

translucent, therefore it allows us to see

through the hair’s natural colour. Eumelanin

is the black and brown pigment, while

phaeomelanin is the pigment responsible for

blond and red.

Product Available to Dye Hair

Temporary colour: this type of colour is found mainly in sprays, gels, water rinses and some

colour shampoos. This colour contains large colour molecules which are too large to penetrate the

cuticle layer of the hair, and it doesn’t contain ammonia, which is used to open the hair cuticles,

allowing the colour molecules to penetrate inside the hair. This type of colour will only last one

wash.

Semi –permanent colour: this type of colour will last between six to eight washes, depending on

the natural hair colour and the tone of the colour used. With eight shampoos the colour will fade.

This type of colour contains a mixture of sizes of coloured molecules, and as it is slightly alkaline

the cuticle scales will open, thus allowing the product to enter the cuticle: the smaller the

molecules, the farther they will travel. So as the hair is shampooed each time, the large molecules

will wash out but the smaller molecules will remain, enabling the colour to last longer.

Permanent colours: these tints, also called oxidation dyes, require the addition of hydrogen

peroxide, otherwise they will not work. The small colourless molecules within the tint enter the

cortex. Once inside, the hydrogen peroxide activates them into joining together to form large

coloured molecules which then become trapped within the cortex. This process can take anything

from thirty minutes to sixty minutes, depending on the product that you are using. If this product

is taken off too soon, it will become semi-permanent.