1,5-NAPHTHALENEDIOL is graded C (Moderate) by Expert·ING, based on COSING regulatory data. It is restricted under EU COSING — AnnexIII-SAFETY-.
1,5-NAPHTHALENEDIOL
Safety grade: C
1,5-Naphthalenediol is a chemical compound derived from naphthalene, a carbon-based ring structure. It appears as a white to light-colored powder that is used in hair coloring products.
This ingredient is used in hair dye formulations as a color coupler, helping to create and develop specific shades when combined with oxidizing agents during the hair coloring process.
Graded using: COSING.
- EU COSING — Restricted
Last verified: May 26, 2026
Safer alternatives to 1,5-NAPHTHALENEDIOL
- 2-METHOXYMETHYL-P-PHENYLENEDIAMINE — Grade A. Oxidative hair dye precursor that develops color when combined with peroxide
- 5-AMINO-6-CHLORO-O-CRESOL — Grade A. Oxidative hair dye precursor that develops specific shades with oxidizing agents
- LAWSONIA INERMIS EXTRACT — Grade A. Natural plant extract used as direct hair dye and color developer in formulations
Other Hair Dyeing ingredients
- RESORCINOL — Grade E**
- THYMOL — Grade A
- M-AMINOPHENOL — Grade C**
- P-AMINOPHENOL — Grade C**
- 2-METHYLRESORCINOL — Grade C
- 4-AMINO-2-HYDROXYTOLUENE — Grade C
- P-PHENYLENEDIAMINE — Grade D**
- 2-METHYL-5-HYDROXYETHYLAMINOPHENOL — Grade C