Hair dye products can normally be placed into four specific categories. These categories are as follows: temporary, semi-permanent, deposit only and permanent.

When using any of these products (except possibly temporary dye), we suggest you perform a patch test on a small area of hair before the main application just to determine whether you are allergic to the particular hair dye color.

Hair lightening, often referred to as bleaching can be described as the chemical process involving the diffusion of the natural color pigment or artificial color from the hair. This process is central to both permanent hair dye and hair lighteners.

All “permanent” hair color products and lighteners contain both a developer, or oxidizing agent, and an alkalizing ingredient as part of their ammonia or an ammonia substitute. The purpose of this is to:

* raise the cuticle of the hair fibre so the tint can penetrate,
* facilitate the formation of tints within the hair fibre,
* bring about the lightening action of peroxide.

When the tint containing the alkalizing ingredient is combined with the developer (usually hydrogen peroxide), the peroxide becomes alkaline and diffuses through the hair fibre, entering the cortex, where the melanin is located. The lightening occurs when the alkaline peroxide breaks up the melanin and replaces it with new color.

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