Hair colour products that involve a chemical change when mixed with a developer are referred to as?

Hair colour products that involve a chemical change when mixed with a developer are known as oxidative colour. This type of colour formulation works through a chemical reaction that occurs when the colour product is mixed with an oxidizing agent, commonly hydrogen peroxide found in the developer. This reaction allows the colour to penetrate the hair shaft and create a longer-lasting change in hair colour.

Oxidative hair colours usually provide more vibrant and enduring results compared to other types of hair colour products since they fundamentally alter the hair's internal structure, resulting in a more permanent effect. This makes them ideal for clients seeking a significant colour change or grey coverage.

Other types of hair colour do not involve this chemical change. Semi-permanent colours typically don't require a developer and fade gradually over time. Temporary colours coat the hair and last for only a few washes, and hair tint can refer to a variety of products but often does not imply a lasting effect that comes from a chemical reaction like oxidative colours do.