Science
Mechanism of Action
Functions as a chemical intermediate that penetrates hair fibers and reacts with oxidizing agents like hydrogen peroxide to create large, stable color molecules trapped within the hair structure. Upon skin contact, acts as a hapten by binding to skin proteins, potentially triggering delayed-type hypersensitivity reactions.
Research
Clinical Evidence
High confidence2%
Key findings
- 01 CIR Expert Panel determined safety for hair dye applications up to 6% concentration in non-sensitized individuals, with typical diluted on-scalp concentrations limited to 1-2%
Transparency
Dusting Analysis
Not applicable for skincare formulations due to safety restrictions limiting use to hair products only
The Formula
Formulation
Stability
Exhibits significant instability when exposed to light and atmospheric oxygen, leading to rapid darkening through oxidation. Hydrochloride salt form enhances water solubility and maintains stability in acidic to neutral pH environments prior to developer activation.
Conflicts
- Oxidizing agents
- Strong bases
- Iron (III) chloride
- Air (oxygen)
- Light
Safety
Safety Profile
Approved exclusively for permanent hair dye formulations. Prohibited in products intended for skin, eyelash, or eyebrow contact due to strong sensitization potential.
Your Skin
Skin Compatibility
Our Assessment
Verdict
Restricted to hair applications only due to high sensitization risk, making it unsuitable for precision skincare formulations.
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References
Sources