Database/Hair Dyeing/HC Blue No. 6
Mostly petroleum · ISO 16128

Is HC Blue No. 6 natural?

Mostly not. The dye core and propanediol side chain are petrochemical; only the chloride counter-ion from the HCl salt counts as mineral/natural mass.

INCI nameHC Blue No. 6
CAS93633-79-5
FormulaC11H18ClN3O4 · 291.73 Da
FunctionHair Dyeing
FeedstockManufactured from petrochemical nitroaniline intermediates reacted with propylene…

How we scored it

C11H18ClN3O4=291.7 Da; nitroaniline-diol core is petrochemical; Cl- counter-ion (35.45 Da) is mineral-origin; 35.45/291.7=0.12
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

Manufactured from petrochemical nitroaniline intermediates reacted with propylene oxide, then salified with hydrochloric acid. No natural-origin route exists for the dye itself.

In plain English

A synthetic dye, made mostly from petroleum-derived chemicals and supplied as a hydrochloride salt, used to add blue color in semi-permanent hair dyes.

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Structure

2D structure of HC Blue No. 6

3-[N-methyl-4-(methylamino)-3-nitroanilino]propane-1,2-diol;hydrochloride

PubChem CID 5463774 ↗

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. 2HC Blue No. 6. PubChem CID 5463774. National Center for Biotechnology Information. pubchem.ncbi.nlm.nih.gov ↗
  3. 3HC BLUE NO. 6. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  4. 4HC BLUE NO. 6. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=HC%20BLUE%20NO.%206