Database/Hair Dyeing/Acid Orange 7
Mostly petroleum · ISO 16128

Is Acid Orange 7 natural?

Mostly not. Naphthol and benzene rings joined by a synthetic azo bond are petrochemical; only the sulfonate salt counts as mineral-origin.

INCI nameAcid Orange 7
CAS633-96-5
FormulaC16H11N2NaO4S · 350.3 Da
FunctionHair Dyeing
FeedstockSynthesised from petrochemical naphthalene and aniline derivatives via…

How we scored it

MW 350; SO3Na fragment ~103Da (mineral, natural) / naphthol-azo-benzene backbone ~247Da (petrochemical) = 103/350=0.29
What counts. ISO 16128-2 scores the atoms that remain in the final ingredient. Reagents, solvents, catalysts and protecting groups used during manufacture leave no mass behind and are not counted.

Where it comes from

Synthesised from petrochemical naphthalene and aniline derivatives via diazotisation and azo coupling. No natural production route exists for this dye.

In plain English

A synthetic orange dye used to colour hair and cosmetics. It is built from petroleum-derived aromatic chemicals through an industrial dye-coupling reaction; no plant or mineral version exists.

CosIng definition: Acid Orange 7 is classed chemically as a monoazo colour (see also CI 15510). It conforms to the formula:

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Structure

2D structure of Acid Orange 7

sodium 4-[(2-hydroxynaphthalen-1-yl)diazenyl]benzenesulfonate

PubChem CID 135442941 ↗

References

  1. 1ISO 16128-1:2016 and ISO 16128-2:2017 — Guidelines on technical definitions and criteria for natural and organic cosmetic ingredients and products. ISO, Geneva.
  2. 2Acid Orange 7. PubChem CID 135442941. National Center for Biotechnology Information. pubchem.ncbi.nlm.nih.gov ↗
  3. 3ACID ORANGE 7. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  4. 4ACID ORANGE 7. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=ACID%20ORANGE%207