Permanent (Oxidative) Hair Color Dyes

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Primary Intermediates

• PPD – Darker & more Intense shades
• PAP – Lighter & Less Intense shades

Couplers

• Blocked – Brighter & more Chromatic Colors (Give shade its characteristic color)
• Unblocked – Drab colors (Used to build intensity without any particular shade characteristics)
• Color Molecules penetrate deep into the cortex where they combine and increase in size making it difficult for them to exit (thus making them permanent)