THE COLOR PALETTE

Any child who draws, any painter starting out, has at some time found himself confronted with the difficulty of faithfully reproducing the colour of hair. The infinity of tints and highlights seems to escape being captured by the conventional palette. Is it therefore fair to reveal that what we strive so hard to reproduce is actually created by nature with no more than two pigments?


  The colour craftsmen

A melanocyte transmitting melanin to a keratinocyte

A melanocyte transmitting melanin to a keratinocyte (confocal microscopy)

The cells responsible for hair colour, the melanocytes , are large star shaped cells, the branches of which are called dendrites. They are mainly found at the bottom of the hair follicle . It is there that they manufacture melanin in the form of small grains of coloured pigment. Then, by lengthening their dendrites, they inject these pigments into the keratinocytes of the hair shaft which is being formed. Thus, from the start, the hair acquires its colour, a colour made to last throughout the life of the hair, i.e. an average of 3 years, with exceptions exceeding some ten years. All the more extraordinary when you realise that a hair contains no more than 1% of melanin!

  Only two pigments
Pigments

Pigments

A melanocyte produces two types of melanin: eumelanin and phaeomelanin .
Eumelanin occurs in the form of a small rice-like granule having a colour varying between browny-red and black. It is generated by an amino acid, tyrosine , being transformed by an enzyme , tyrosinase .

Phaeomelanin has a less precise shape and can be seen in the form of diffuse spots. Its colour varies from yellow to red. It differs from eumelanin, because, in addition to tyrosine, another amino acid is involved in its production, known as cysteine , which is rich in sulphur.

  The infinite palette
eumelanin and phaeomelanin



The proportions of these two melanins determine the colour of the hair. But, while it is easy to understand that Japanese black hair contains virtually only eumelanin and that Irish red hair is very rich in phaeomelanin, it is more surprising to discover that Scandinavian blond hair is also mainly formed from eumelanin.

This is linked to the immense range possible in the mixtures of the two pigments, a range in terms of type as well as quantity. So the distribution of melanins, determined by each person's genetic inheritance, offers an infinite palette ranging from the lightest blond to the deepest black.

One major question of course remains: what about grey hair




WELCOME
PORTRAIT OF AN UNKNOW ELEMENT
LIVING AND RELIVING
AMAZINGLY NATURAL

THE COLOR PALETTE

THE SHAPE WORKSHOP

HAIR - OR FUR ?

THERE'S NO SUCH THING AS GREY HAIR
SO STURDY AND YET SO FRAGILE
INFINITE TRANSFORMATIONS
THE HAIR A SCIENTIFIQUE ENIGMA
HAIR AND CULTURE
EXHIBITIONS
TOOLBOX







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