CI 17200 is a synthetic water-soluble pigment, commonly known as Acid Red 33, used to impart a pink to red hue to cosmetic products. This coloring agent ensures visual consistency and aesthetic appeal in aqueous formulations like toners, cleansers, and shampoos.
- INCI Name:
- CI 17200
- Chemical/Scientific Name:
- Disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate
- Common Aliases:
- D&C Red No. 33, Acid Red 33, Red 33
| Category: | Colors |
| Source Origin: | Synthetic (Azo dye) |
| Comedogenic Rating: | 0 |
| Primary Industries: | Skincare, Haircare, Cosmetics, Personal Care |
| Solubility: | Water-soluble |
At a Glance: Properties & Effects
| Texture Enhancement: | |
| Formula Stability: | |
| Irritation Risk: | |
| Comedogenicity: |
- Primary Benefits: Aesthetic coloring, formula standardization, high water solubility.
- Potential Risks: Minimal risk of skin sensitivity in hyper-reactive individuals; regulated usage limits.
Biological Action & Cosmetic Profile
Azo dyes such as CI 17200 function by absorbing light in the visible spectrum, specifically reflecting wavelengths that the human eye perceives as red or bluish-red. This molecule is a disodium salt characterized by high polarizability, which grants it excellent solubility in Aqua based systems. Because the molecule is relatively large and highly ionized, it does not penetrate the skin barrier or interact with underlying biological pathways. Its presence is purely functional for the exterior presentation of the cosmetic medium.
Stability remains a hallmark of this pigment in various environments. The chemical structure resists significant fading when exposed to moderate light, though long-term UV exposure can eventually degrade the azo bond. Formulators often pair this dye with chelating agents like Disodium Edta to prevent metallic ions from altering the intended shade. In emulsions containing Glycerin, the dye remains suspended in the water phase, providing a clear and vibrant tint without clouding the solution.
Broader Applications & Origins
Usage of this colorant extends across the entire personal care sector, ranging from mouthwashes and soaps to high-end serums. Regulatory bodies like the FDA classify it as D&C Red No. 33, permitting its use in drugs and cosmetics. However, specific regional restrictions may apply; for instance, in the United States, it is not permitted for use in the area of the eye. Its synthetic origin allows for a high degree of purity and batch-to-batch consistency that natural pigments often lack.
Routine Integration
- Synergies: Works optimally in formulations using Citric Acid for pH adjustment, as it maintains color integrity in slightly acidic environments. It is frequently combined with other water-soluble dyes to achieve specific secondary colors like purple or orange.
- Conflicts: Strong oxidizing agents or high concentrations of Ascorbic Acid may lead to color reduction or “bleaching” over time.
Clinical Consensus & Safety
The Cosmetic Ingredient Review (CIR) Expert Panel and the European Commission’s CosIng database recognize CI 17200 as safe for use in cosmetic products when meeting specific purity requirements (such as limiting aniline impurities). Clinical data indicates that the dye is a non-sensitizer and non-irritant for the vast majority of the population. Extensive toxicological testing confirms that the ingredient does not pose a risk of systemic toxicity due to its negligible dermal absorption profile.
Is CI 17200 safe for sensitive skin?
Yes, CI 17200 is generally considered safe for sensitive skin as it does not penetrate the skin barrier and has a very low incidence of irritation. However, individuals with known dye sensitivities should perform a patch test.
Why is this dye used instead of natural colors?
Synthetic dyes like CI 17200 offer superior stability, color intensity, and resistance to pH changes compared to many natural alternatives, which can brown or fade quickly in a bottle.
Can CI 17200 stain the skin?
At the very low concentrations used in skincare (typically less than 0.1%), this pigment will not stain the skin. It is designed to remain in the product vehicle and wash away easily with water.