The Journal

Notes from the laboratory.

Chemistry and craft behind every BioHueZ formulation.

Allergic reaction to hair dye: a guide to PPD sensitivity.
FeaturedSafety

Allergic reaction to hair dye: a guide to PPD sensitivity.

How to recognise the symptoms of an allergic reaction to hair dye, why PPD is almost always the culprit, and what hair dye not containing PPD actually looks like at the molecular level.

June 2026 · 7 min read
Beyond PPD: The molecular secret to safe hair color.
Chemistry

Beyond PPD: The molecular secret to safe hair color.

May 2026 · 9 min
Coating vs. rebuilding: the chemistry of true post-color repair.
Repair

Coating vs. rebuilding: the chemistry of true post-color repair.

April 2026 · 5 min
Beyond the scent: the dirty secret of 'ammonia-free' color.
Formulation

Beyond the scent: the dirty secret of 'ammonia-free' color.

March 2026 · 8 min