Chapter 7 – Corrective Colour
7.2 Tint Back
A tint-back service is the process of returning pre-lightened hair to a darker shade with the help of a filler. A tint-back process is necessary when the hair is being coloured three or more levels darker or when the pre-lightened hair requires a filler to correct an unwanted blue or violet muddy tone.
Filler
A filler is used to:
- Equalize the porosity of prelightened hair.
- Replace the missing underlying pigment that was removed during the lightening process.
There are two types of fillers. One is applied and fully processed prior to the target colour application and can be either non-oxidative or oxidative, depending on hair texture and integrity. The second type of filler is a liquid tint that is applied to the hair, with the final colour formula applied directly over it.
A filler is a useful tool in equalizing the porosity of pre-lightened hair before the final colour service. Porous hair accepts colour more easily, but also tends to lose it more quickly. Additionally, if hair has unequal porosity from roots to ends, the resulting colour will be uneven.
When hair is lightened, we know that the bleach product will diffuse the natural melanin in the cortex and remove it, exposing the warm underlying pigment in our ten levels.
For example, if the hair is lifted from a level 4 to a level 8, all red and orange underlying pigment is removed, and we are left with yellow.
Now imagine that we want to reverse the process and perform a tint back to bring that level 8 hair to a level 4. We must add back that missing pigment in order to create the most balanced result.
Using the above scenario, let’s suppose the client would like a neutral–cool toned level 4 result. What would happen if you simply applied a blue-based level 4 onto the pre-lightened yellow hair?
Think back to the colour wheel: Blue + Yellow = Green… Not a very attractive result!
So how do we formulate our filler?
Generally, we want to fill to two levels lighter than our target end result. Consider the examples below:
If the hair is filled to 2 levels lighter than the target of level 4, you will need to add back the underlying pigment at a level 6, which is orange. Let’s say for this scenario that you decide to use a semi-permanent filler, for example a level 6 copper. You will apply this filler to the pre-lightened hair, process fully, then remove.
So now, after the filler process, you have a level 6 copper/orange:
If you refer back to the colour wheel, you see that orange and blue are complimentary colours. Therefore, you can now apply a level 4 ash colour to create a neutral-cool result!
Will you always need to neutralize your filler tone? Generally a neutral or natural-warm result will not require neutralization, but a cool tone will.
As mentioned above, a filler is also helpful when a client wants to go darker, but has pre-lightened hair that is over-toned and has a muddy blue/purple cast to their blonde hair. In this case, the filler also