Hair decolorizers

Hair decolorizers are used for hair care . They are used for bleaching colored hair. Depending on the type of coloring, different means must be used. The ingredients of such agents must be declared on the packaging. This is regulated by the Directive "International Nomenclature of Cosmetic Ingredients" (abbreviation INCI from English. International Nomenclature of Cosmetic Ingredients ).

Herbal hair colors

Herbal hair colors are removed with oxidative bleaching. 4–6% hydrogen peroxide solutions are used for this.

Metal salt hair colors

Metal salt hair dyes can only be removed using complex chemical processes. For example, silver salt stains are removed with alkali , potassium iodide and sodium thiosulphate .

Oxidation colors

Declaration of the ingredients of a hair lightener (oxidizing agent) according to INCI

Oxidation hair dyes can be peeled off with reducing agents in acidic solution or overoxidized with oxidizing agents in alkaline solution.

Reducing agent

When reducing agents are applied in acidic solution, the oxidation dyes are split reductively, which can then be washed out. The natural pigments remain unchanged. In this process, however, not all of the split oxidation dyes can be washed out. As a result, the hair darkens again after a while, as the breakdown products are oxidized again by the oxygen in the air.

Oxidizing agent

In contrast to decolorization with reducing agents, this is a bleaching process, whereby all natural color pigments are destroyed. A short exposure time for hydrogen peroxide solutions is sufficient for light colors. In the case of dark colors, a hydrogen peroxide peroxodisulphate shampoo must also be used.

Direct dyed hair

The discoloration can already be achieved with normal shampoo washes. If this does not succeed, a strand-wise treatment with ethanol can help.

Individual evidence

↑ Aebi, Hugo., Baumgartner, Erich: Cosmetics, fragrances and food additives . Thieme, Stuttgart 1978, ISBN 3-13-562101-4 , p. 24 .
↑ ^a ^b ^c ^d ^e ^f Franz, Manfred .: Chemical products in everyday life: Essen u. Drinking, health and Body care, cleaning, fertilization, etc. Pest Control . German Taschenbuch-Verlag et al., Munich 1985, ISBN 3-423-03276-6 , pp. 210-212 .

[1] Aebi, Hugo., Baumgartner, Erich: Cosmetics, fragrances and food additives . Thieme, Stuttgart 1978, ISBN 3-13-562101-4 , p. 24 .

[:0-2] ↑ ^a ^b ^c ^d ^e ^f Franz, Manfred .: Chemical products in everyday life: Essen u. Drinking, health and Body care, cleaning, fertilization, etc. Pest Control . German Taschenbuch-Verlag et al., Munich 1985, ISBN 3-423-03276-6 , pp. 210-212 .