What does a toner do in hair coloring?

A toner plays a crucial role in hair coloring by adjusting the tone of the color. After the primary hair coloring process, which might involve lightening or depositing color, a toner is applied to refine the resulting shade. This is particularly important in achieving the desired hue, as it can neutralize unwanted undertones, such as brassiness in blonde hair or warmth in cool shades. Toners can shift the overall appearance of a color from warm to cool or vice versa, allowing for a more customized and aesthetically pleasing result.

While other options may pertain to aspects of hair treatment and coloring, they do not accurately describe the specific function of a toner. For instance, lightening hair is a separate process typically performed with bleach rather than toner. Enhancing shine may be a side effect of using a toner, but it is not the primary purpose. Providing moisture, while essential for hair health, is not a characteristic feature of toner products, which are focused on color adjustment.