Colorants in cosmetics are substances used to impart color to cosmetic products, enhancing their aesthetic appeal and allowing for product differentiation but colorants are essential for some products like foundations, lipsticks, eye shadows, blushes, nail polishes, and more. Their chemical nature influences factors like opacity, texture, longevity, and compatibility.
The colors used in the cosmetic industry must be of the D&C or FD&C type and must have the approval of regulatory agencies (such as FDA). Just as the raw materials in this industry are identified with INCI, the colors also have a CI (Color Index) code for identification.
The colors used in products are Dye or Pigment. Dyes are water-soluble, oil-soluble, and are used in emulsions and water- and alcohol-based products. In contrast to Dyes, Pigment colors are insoluble in liquids and are suspended in formulations and are used in products such as lipsticks, eye shadows, and powders. Dyes are mainly synthetic, but Pigments have a mineral or organic base. Lake colors are actually Dye colors that have been placed on a metal substrate and made insoluble. These colors are dispersed in solution and are more stable than Dyes and are used in powder or low-water products.
Dyes are also divided into inorganic and organic, which can be synthetic or natural.
Organic dyes are mainly synthetic and cover a wide range of colors, but inorganic dyes, which can be synthetic or natural metal compounds, offer a limited range of shades and have limited applications.
There are also a limited number of dyes that are obtained from plants.

In the U.S., colorants must be approved by the FDA under Title 21 CFR Parts 70 to 82
In the EU., List of colorants allowed in cosmetic products is in ANNEX IV of COSING DATABASE.