Database/Hair Dyeing/Basic Orange 31
Mostly petroleum · ISO 16128

Is Basic Orange 31 natural?

Mostly not. Synthetic imidazolium azo hair dye supplied as a salt. Only the chloride counter-ion counts as natural origin under the site's mineral counter-ion convention; every carbon in the coloured cation is petrochemical.

INCI nameBasic Orange 31
CAS97404-02-9
FormulaC11H14ClN5 · 251.71 Da
FunctionHair Dyeing
FeedstockPetrochemical aromatic amines and couplers assembled into the…

How we scored it

Basic Orange 31 C11H14ClN5 251.7 Da: chloride counter-ion Cl 35.5 Da is mineral-derived (natural); the imidazolium azo dye cation 216.3 Da is built entirely from petrochemical aromatic intermediates → 35.5/251.7 = 0.14.
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

Petrochemical aromatic amines and couplers assembled into the dye cation, isolated as its salt.

In plain English

A synthetic orange dye used in semi-permanent hair colour products. It's produced from petrochemical aromatic raw materials in a factory process.

CosIng definition: Basic Orange 31 is the hair colorant that conforms to the formula:

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Structure

2D structure of Basic Orange 31

4-[(1,3-dimethylimidazol-1-ium-2-yl)diazenyl]aniline chloride

PubChem CID 9881454 ↗

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. 2Basic Orange 31. PubChem CID 9881454. National Center for Biotechnology Information. pubchem.ncbi.nlm.nih.gov ↗
  3. 3BASIC ORANGE 31. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  4. 4BASIC ORANGE 31. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=BASIC%20ORANGE%2031