1. CASSIE VENABLE ALEXIS TEPLICK Hair Dye

2. Chemicals in Hair Dye NH 3 (Ammonia) H 2 O 2 (Hydrogen Peroxide) Structure at right shows the dinitrodiphenylamine derivative used as dye in semi-permament hair coloring product

3. Hair Composition The hair shaft consists of:  Cuticle  Cortex  Mendulla

4. When Hair Dye Meets Hair Shaft Ammonia (NH 3 )  Alkaline chemical that separates cuticle scales and allows dye to enter cuticle Dye intermediates penetrate cuticle to be oxidized to form larger color molecules  Diaminobenzene  Aminohydroxybenzene  Dihydroxybenzene

5. Hair Dye Meets Hair Shaft H 2 O 2 + 2H + + 2e - 2H 2 O  Equation representing Hydrogen Peroxide as an oxidizing agent (a reactant that accepts electrons from another reactant) Hydrogen Peroxide (H 2 O 2 ) reacts with the color molecules to create new hair color  Reaction catalyzed by Ammonia (NH 3 )

6. Hair Dye Meets Hair Shaft H 2 O 2 is the oxidizing agent  Oxidizes melanin (pigment found in hair) Oxidized melanin becomes colorless New color from dye is then deposited into hair cortex

7. Bonds in Hair Salt Bond Disulphide Bond Hydrogen Bond

8. Hair Dye Meets Hair Shaft H 2 O 2 breaks down chemical bonds in hair, releasing Sulfur (S 8 ) Sulfur is responsible for the distinctive smell of hair dye Conditioner or alcohol seals the cuticle after the dying process is complete to encase and protect new hair color