PHENYL METHYL PYRAZOLONE is graded C (Moderate) by Expert·ING, based on COSING regulatory data. It is restricted under EU COSING — AnnexIII-SAFETY-.
PHENYL METHYL PYRAZOLONE
Safety grade: C
This is a synthetic chemical compound used in hair color products to help create and stabilize hair dye colors. It works as a chemical building block that combines with other dye components to produce the desired color on hair.
This ingredient acts as a color coupler in hair dyes, allowing it to react with oxidizing agents to develop and fix permanent or semi-permanent hair color onto the hair shaft.
Graded using: COSING.
- EU COSING — Restricted
Last verified: May 26, 2026
Safer alternatives to PHENYL METHYL PYRAZOLONE
- 2-METHOXYMETHYL-P-PHENYLENEDIAMINE — Grade A. Direct substitute: oxidative hair dye precursor that couples with oxidizers to develop permanent color.
- 5-AMINO-6-CHLORO-O-CRESOL — Grade A. Oxidative dye intermediate: amino-substituted phenol that acts as color coupler in permanent hair dyes.
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