Common Name(s): Ci 64500,anthraquinone blue
CAS Number: 2475-45-8
DESCRIPTION
What It Does: Provides stable blue semi-permanent hair colour with improved wash fastness from anthraquinone structure.
Why It's Used: More wash-fast blue direct hair dye for improved longevity in semi-permanent blue hair colour formulations.
How It Works: Anthraquinone chromophore provides better photostability and wash resistance than nitro-based direct dyes. adsorbs to hair via van der waals and electrostatic interactions. blue colour from anthraquinone 620nm absorption.
Typically Found In: Semi-permanent hair colour,fashion blue hair
TECHNICAL DETAILS
Primary Category: Hair colourant โ direct dye
Secondary Functions: Skin conditioning
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: 0.1%โ2%
SOURCING & ETHICS
Vegan Status: Conditional - supplier confirmation required
Halal Status: Unverified - supplier confirmation required
Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier. [audit 2026-07-29 rev2: the record's own source_notes does not assert a non-animal origin, or instructs the reader to verify with the supplier; "yes" asserts knowledge the record does not hold. determination requires shariah-panel sign-off.]
SKIN COMPATIBILITY
Irritancy Rating: 1/5 โ very low
Comedogenicity Rating: 0/5 โ non-comedogenic
Sensitivity Concerns: Well-tolerated by most skin types.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Eu annex iii restricted. warning label required.
Works Well With: Standard skincare actives
Avoid Combining With: No known significant incompatibilities
SCIENTIFIC NOTE
Disperse blue 1's anthraquinone structure provides superior wash fastness to direct nitro-dyes because anthraquinone's larger, flatter molecular structure provides stronger van der waals contact area with keratin's flat beta-sheet protein surface. the greater surface contact area provides higher adsorption energy that resists displacement by water and shampoo surfactants better than smaller nitro-dye molecules.
Last Verified: 2026-03-12
Primary Sources: Cosing database,eu annex iii hair dye list