Colorant

Basic Yellow 40

INCI: BASIC YELLOW 40
CAS 29556-33-0 EC 249-694-9
2-[7-(Diethylamino)-2- Oxo-2H-1- Benzopyran –3-yl]-1,3-dimethyl-1H-Benzimidazolium Chloride
Limited Data
Insufficient safety data available. Consider enriching this ingredient.
Details

Description

2-[7-(Diethylamino)-2- Oxo-2H-1- Benzopyran –3-yl]-1,3-dimethyl-1H-Benzimidazolium Chloride

Purpose

Function

Hair dyeing (semi-permanent cationic dye)
Profile

Properties

Silicone
Silicone free
Compliance

Regulatory Status

EU
Banned
Safety
POOR
US
Permitted
Absorptionlow
Sensitizationlow
MoSnot established
NOAEL996 mg/kg
ConcernModerate
Verdict

Coumarin-benzimidazolium hybrid structure; verify fluorescence behavior does not interfere with product claims; respect concentration limits

US Note

Exempt under coal-tar hair dye provision; caution labeling required

Assessment

Ratings

Comedogenic0/5
LowHigh
Irritancy0/5
LowHigh
Reference

Identifiers

CAS Number
29556-33-0
EC Number
249-694-9
INCI
BASIC YELLOW 40
Category
Colorant
Updated
Apr 2, 2026