Red 4 ●
TL;DR. This ingredient is a synthetic color additive used to give formulas a red to pink hue. Its role is visual only, not skin-conditioning, cleansing, or preservation.
What does Red 4 do in a cosmetic formula?
This ingredient is a synthetic color additive used to give formulas a red to pink hue. Its role is visual only, not skin-conditioning, cleansing, or preservation.
Is Red 4 clean?
This ingredient has clean-standard friction because many clean frameworks restrict certified synthetic colorants, especially azo dye chemistry. It can also raise sensitivity questions for a small subset of users, and its use is regulated by region and application area.
Is Red 4 sustainable?
This material is made through synthetic organic chemistry, typically from petrochemical aromatic feedstocks rather than renewable botanical sources. Water-soluble azo colorants can be slow to biodegrade and can add color load to manufacturing wastewater if not well managed.
Is Red 4 COSMOS-approved?
This ingredient is not permitted under COSMOS-natural or COSMOS-organic colorant rules, which favor natural colorants and approved mineral pigments. From a Green Chemistry view, its petrochemical feedstocks and limited biodegradability make it a weak fit.
How does Red 4 work chemically?
The molecule is a sulfonated azo dye, with an azo linkage connecting aromatic ring systems and sulfonate groups that make it water soluble. It is generally used at low tinting levels, is more compatible with aqueous systems than oil phases, and can be affected by strong oxidizers, reducers, certain pH conditions, or metal ions that shift shade or fade color.
Last updated 2026-05-13