Oxidation dyes are primarily aromatic compounds, that belongs to
three major chemical families given here under:
- Diamines
- Aminophenols (amino naphthols)
- Phenols or naphthols
Oxidation dyes are generally colourless, and are typically a low
molecular weight product. Primarily its usage lies as a very popular
colourant material. It forms the basis of the hair dyes. This is because
the oxidation dyes has the property to cover up grey and achieve long
lasting results. They give a wide array of colour range that includes
colour enhancement, grey control and fashion colours. In the context of
hair dyes, Oxidation dyes have been found just right for permanent and
demi-permanent or semi-permanent applications.
![Oxidation Dyes](image2/hair-color.jpg)
Oxidation
dyes falls under two categories, namely oxidation base (primary
intermediate) and coupler (secondary intermediate). For generating
colour using these types, it is essential to use at least one type of
each and mix it with a perfect oxidant under alkaline conditions. This
would ensure the best results. Oxidation dyes often depends on a
solution of dye intermediates like p-phenylenediamine for achieving the
perfect colours. Another important ingredient is hydrogen peroxide.
Typically a higher volume of peroxide in the dye has been seen to give a
lighter and faster result.
To formulate a high quality oxidation dye product
with optimum results, the following points need to be taken care of:
- A thorough understanding of the oxidative condensation process.
- For hair dyes, considerable experience with a fair number of
practical trials. This should take into account various kinds of
hair type.
- A delicate balance among:
- Bleaching strength
- Nature of the dye precursors
- Quantity of ammonium used
The draw back of the Oxidation type of hair dye, is
it's supposedly harmful effects on the hair structure. Which results in
the need for using another product to repair damages as a result of high
alkalinity and strong oxidizing agents.