Colouring Agent/Pigment

CI 19140

Reviewed by Daisy · Last updated 14 Aug 2026

A synthetic yellow colourant used to add visual appeal to skincare formulations

Best For Skin Types

All

Usage Frequency

As part of regular skincare routine

What Is CI 19140?

CI 19140, commonly known as tartrazine or FD&C Yellow No. 5, is a synthetic azo dye widely used in cosmetics and food products as a colorant. It is a bright yellow pigment that serves purely aesthetic purposes in skincare formulations, helping to create visually distinctive products without any direct therapeutic benefit to the skin.

In skincare products, this ingredient functions solely as a cosmetic colorant to enhance the appearance of creams, serums, gels, and other formulations. It does not penetrate the skin or provide active skincare benefits.

How It Works

CI 19140 works through simple light absorption and reflection, giving products their characteristic yellow colour. It remains in the product matrix rather than being absorbed into the skin, making it a purely cosmetic rather than functional ingredient.

Clinical Evidence & References

There is no clinical evidence that CI 19140 provides benefits to skin health or appearance when applied topically in skincare products. The ingredient's sole function is cosmetic colouring.

Research does document that tartrazine can trigger adverse reactions in susceptible individuals through ingestion, primarily affecting those with a history of atopy or sensitivity to azo dyes. However, topical application in cosmetic products represents a different exposure route and risk profile than oral consumption.

How to Use

CI 19140 requires no special application technique, as it is a passive ingredient within the formulation. Simply use the product as directed. If you have a known sensitivity to azo dyes or tartrazine, check the ingredient list before use, though topical reactions are uncommon.

Safety & Precautions

Generally well-tolerated in topical skincare products. Those with documented sensitivity to tartrazine or azo dyes should avoid products containing this ingredient as a precaution, though topical reactions are rare.

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