Direct dyes rely on a relatively smooth hair surface for an even, reflective finish. The three added ingredients each play a practical role:
Keratin: A protein that temporarily fills gaps in the cuticle. By smoothing the outer layer, it reduces the microscopic roughness that can make colour look patchy or dull. The result is a more uniform violet tone and less post-colour roughness.
Vitamin E (tocopherol): Functions as an antioxidant in the formula. It helps stabilise the dye base against oxidation during storage and, on the hair, can mitigate some of the oxidative stress from environmental exposure (UV, pollution) that contributes to premature fading.
Linseed oil: Rich in omega-3 fatty acids, it coats the hair shaft with a light, flexible film. This improves slip during application, reduces friction during rinsing, and leaves a noticeable shine boost once the hair dries.
Together, these ingredients mean you are not just depositing pigment — you are also giving the hair a conditioning treatment in the same step. However, they do not replace a dedicated deep-conditioning mask if your hair is significantly damaged; think of them as a supportive bonus rather than a repair solution.