Basic Green 4

What is Basic Green 4?

Basic Green 4 is a synthetic triarylmethane derivative, classified as a cationic direct dye with the Colour Index CI 42040. It originates from chemical synthesis and belongs to the class of basic dyes valued for their strong affinity to hair keratin due to positive charge. Primarily used in semi-permanent and temporary hair color formulations, it functions by physically adsorbing onto the hair cuticle, providing immediate color deposition without requiring oxidation or peroxide developers. This allows for bright green hues that fade with washes, supporting creative styling like highlights or full coverage. Its water-soluble nature ensures even distribution during application, while stability in alkaline conditions aids rinse-off performance in shampoos or conditioners.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 8 View on EWG →
PubChem View on PubChem →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Hair colorant
Delivers hair color through dyes and/or pigments (direct or oxidative systems), producing a visible shade change and supporting coverage and longevity.
Hair dyeing
Supports chemical color change of hair (e.g., oxidative dye development or bleaching), enabling shade transformation through controlled reactions on the fiber.

Benefits

Provides intense, vibrant green color to hair for creative expression.

Offers direct dyeing action for quick, no-commitment shade changes.

Supports color longevity on hair fibers through strong binding affinity.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
Individuals seeking bold, temporary green hair shades.
People with known allergies to hair dyes.
People experimenting with semi-permanent hair coloring.
Individuals with sensitive scalps prone to irritation.
Those preferring non-oxidative dye systems for gentler application.
Those with a history of contact dermatitis from colorants.

Safety Notes

  • Rated high concern by EWG due to potential toxicity data.
  • Patch testing advised before full use in hair products.

Frequently Asked Questions about Basic Green 4

What is Basic Green 4 used for?

It serves as a hair colorant and dyeing agent in semi-permanent products for green shades.

Is Basic Green 4 safe for all hair types?

High hazard rating suggests caution; suitable for non-sensitive users with patch testing.

How does Basic Green 4 apply to hair?

It deposits color directly onto hair without chemical reactions, fading with washes.