Application of Dyes and Pigments
Colourants for Cosmetics Industry
Dyes have found a wide variety of uses in the cosmetics industry. Be it the hair dyes or lipsticks or nail polish shampoo everywhere there is wide use of dyes. Let us look at hair dyes. Most of the commercial hair dye formulas available now are complex, that uses bunchful of ingredients, and the formulas also differ considerably with manufacturers. Since we are interested in the dye part let's see what kind of dyes are used in making of hair dye. The dye chemicals that are used usually consists of amino compounds, like 4-amino-2-hydroxytoluene and m-Aminophenol. Pigments of Metal oxides, like titanium dioxide and iron oxide, are also used. The process of manufacturing hair dye is illustrated in this diagram.
In the category of decorative cosmetics, the majority of colors used are pigments. It is the inorganic pigments that are popular with cosmetics but are subject to purity levels of heavy metals. The range of inorganic pigments used in cosmetics is generally made up of various chemical types. A few of the popular ones is provided in the table.
In addition to this some types of organic pigments are also used along with water soluble and oil soluble dyes in the cosmetics application.
Some examples of water soluble dyes are given here.