Demi-Permanent hair color uses what to develop the color molecules and aid processing?

• A. Hydrogen peroxide 20 volume
• B. Ammonia
• C. Low Volume Hydrogen Peroxide
• D. No developer

Answer: (C)

The key idea is how a small amount of oxidizing agent activates and builds the color molecules without lifting the hair color. Demi-permanent color uses a low-volume hydrogen peroxide to gently oxidize the dye precursors so they form the final pigment and deposit into the cortex. This mild developer provides enough processing power to develop the color but not enough to lift the existing color, which is why the result fades with washing rather than growing lighter. Using a higher-volume peroxide would lift natural pigment and create a permanent color, while ammonia would open the cuticle more aggressively, and no developer would leave the dye unoxidized and ineffective for this type of color.