Acid Orange 7

Safety Information

Acid orange 7, when certified by the Food and Drug Administration (FDA), is referred to as orange 4 and can be used in coloring externally applied cosmetics. Please refer to orange 4 for more information on the certified color.

Additional information about the safety of hair dyes.

In the European Union, acid orange 5, as CI 15510, is permitted for use in cosmetic products with the exception of products used around the eyes (see Annex IV).


Acid Orange 7

What Is It?

In cosmetics and personal care products, acid orange 7 is used in the formulation of hair coloring products.

Why Is It Used?

Acid orange 7 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

Acid orange 7 is a synthetic pigment sometimes referred to in general terms as a monoazo color.

Hair dyeing formulations belong to three categories – temporary, semi-permanent and permanent coloring of hair. The permanent hair dyeing formulations are often referred to as oxidative hair dyes which are generally marketed as two-component products. One component contains the compounds (precursors) that become the colorants and the other component is a stabilized solution of hydrogen peroxide. The two components are mixed immediately prior to use. The precursors and peroxide diffuse into the hair shaft, where color formation takes place after the ingredients combine to produce the coloring mixture. The precursors are oxidized by the hydrogen peroxide to form the colorant molecules. These molecules are too large to escape from the hair structure. The hydrogen peroxide in the oxidative hair dye product also serves as bleaching agent for the natural pigment of the hair. The color that is formed depends on the precursors and direct dyes present in the dyeing solution, pH of the dyeing solution and the time of contact of the dyeing solution with the hair.