4-NITRO-O-PHENYLENEDIAMINE HCL is graded A (Safe) by Expert·ING, based on COSING regulatory data.
4-NITRO-O-PHENYLENEDIAMINE HCL
Safety grade: A
This is a synthetic chemical compound used as a color agent in hair dye products. It belongs to a family of chemicals that react with other dye components to create lasting color inside the hair shaft.
It is used in permanent and semi-permanent hair dyes to deposit color into the hair, helping to achieve a range of shades from warm browns to reddish tones.
Graded using: COSING.
Last verified: May 26, 2026
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