What is the function of a developer in hair color and how does its strength affect lift and deposit?

• A. The developer colors the hair; higher volume produces deeper color
• B. The developer supplies oxidizing agents; higher volume lifts more but increases potential damage; lower volume deposits color with less lift
• C. The developer is a conditioning agent; higher volume moisturizes
• D. The developer changes natural level; volume sets shade

Answer: (B)

Developers provide the oxidizing power that activates color molecules and determines how much lifting versus depositing happens during a color service. In permanent color, the developer—typically hydrogen peroxide—oxidizes the color precursors and helps open the cuticle so pigment can enter the hair shaft. The strength of the developer, expressed as volume, controls this balance: higher volume delivers more lift, lightening the natural pigment more but also increasing the potential for damage because more oxidation occurs. Lower volume results in less lift and more pigment deposition, producing color with less lightening and typically less stress on the hair. This is why the described function fits best: it supplies the oxidizing agents, and its higher volume lifts more while raising the risk of damage, whereas lower volume deposits color with less lift.