Which type of developer is appropriate for thick, coarse hair?

Using a higher volume developer, such as 30 or 40 volume, is particularly appropriate for thick, coarse hair because this hair type tends to have a more resistant cuticle structure. The cuticle layer in thick, coarse hair is often tightly closed, which can make it more challenging for color to penetrate effectively.

Higher volume developers contain a greater proportion of hydrogen peroxide, which enables them to lift the hair's natural pigment more intensively and activate the color. This is essential for ensuring that color formulations work efficiently on thick and coarse hair, providing the necessary lift and penetration for achieving the desired shade.

In contrast, lower volume developers are better suited for finer or porous hair, where minimal lift is needed, and may not be effective for thicker strands that require a stronger formulation for optimal results.