Disperse Black 9

What Is It?

Disperse Black 9 is a monoazo color used in the formulation of semi-permanent hair dyes and hair coloring rinses.

Why Is It Used?

Disperse Black 9 imparts color to hair. The exact color obtained will depend on the other ingredients that are used in the preparation and the starting color of the hair.

Scientific Facts

Disperse dyes get their names from the fact that they are used in dye baths as colloidal (particle) dispersions. Disperse Black 9 is used in semi-permanent hair coloring systems where color is deposited or adheres to the hair shaft.

Safety Information

The safety of Disperse Black 9 has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Disperse Black 9 was safe for use as a hair dye ingredient. In 2006, as part of the scheduled re-evaluation of ingredients, the CIR Expert Panel considered available new data on Disperse Black 9 and reaffirmed the above conclusion.

CIR Safety Review:

Disperse Black 9 was slightly toxic to practically nontoxic when administered orally and practically nontoxic when administered intraperitoneally. The dye was nonirritating to the eyes and skin and was not sensitizing. A 3% suspension of the dye produced no irritation or sensitization in human subjects. Disperse Black 9 was nonmutagenic in four different assay systems. A laboratory test on a hair dye formulation containing Disperse Black 9 indicated that the compound was not not carcinogenic when applied dermally. The CIR Expert Panel concluded that Disperse Black 9 was safe for use as a hair dye ingredient.

More information about the safety of hair dyes .

In the European Union, Disperse Black 9 is permitted for use in non-oxidative hair dye products at a maximum concentration of 0.3%. See Annex III for more information about the use of Disperse Black 9 in hair dye products in Europe.

Link to the EU Cosmetic Regulation: http://europa.eu/legislation_summaries/consumers/product_labelling_and_packaging/co0013_en.htm

More Scientific Information

Hair dyeing formulations belong to three categories — temporary, semi-permanent and permanent coloring of hair. Temporary coloring preparations, often called color rinses, provide color which lasts until the first shampooing. Ingredients which impart temporary color may have a fairly high molecular weight and are unable to penetrate the hair shaft.

These materials are simply deposited onto the hair fiber and are removed by subsequent shampooing. Semi-permanent coloring preparations generally provide color through several shampooings. These materials are often low molecular weight pre-formed dyes which can penetrate the hair shaft to some extent.