How long to leave hair dye on grey roots

How long to leave hair dye on roots? It depends on the color

How long to leave hair dye on grey roots

  • If you are coloring your roots for the first time, you should leave the dye on for 20 to 45 minutes depending on the type and color of the product. I’ll tell you more about the differences later on.
  • Alternatively, to only touch up the roots, you should leave the dye for 20 to 30 minutes. However, it’ll also depend on the type and color of the product you choose.

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What happens if you leave hair dye in too long? Two things could happen

Regarding how long to leave hair dye on roots, we must make two differences:

  • Is it the first time you dye your roots, or do you just want to touch up the color?
  • What type of dye will you use? It could be permanent, semi-permanent, or demipermanent. Their exposure times are different for each.

It sounds like you’re about to take the hardest test of your life.

But don’t worry. Today, I’ll explain in detail everything you need to know about how long you should leave the dye on your roots.

 Why is it important to respect the exposure time of the hair dye on the roots?

Because the roots are the new hair, you need to be careful not to dry them out.

If you follow the instructions regarding the exposure times of the dye, you won’t have frizz. Also, you’ll avoid weakening the hair.

  Remember that the roots absorb dye faster than the rest of the hair. 

If you want to dye your gray hair, you must also respect the exposure times because gray hair is even weaker than the rest.

So, to touch up your roots at home, you should respect the exposure times recommended by each manufacturer.

One more aspect should be considered. Dyeing your roots dark isn’t the same as dyeing them with a very light color.

 The darker the color you apply to your roots, the less time you should leave the dye to act. 

And that is the same for all types of dye.

The roots absorb the pigmentation of darker colors quickly.

Have you decided what color you want to dye your roots, and what type of dye you will use?

Then, let’s get started.

Tabla de Contenidos

  • If you color your roots permanent, you should leave the dye on for 20 to 45 minutes
  • If you dye your roots with demipermanent dye, you should leave it on for 20 to 30 minutes
  • If you dye your roots with a semi-permanent dye, leave it on for 20 minutes
  • Conclusions

If you color your roots permanent, you should leave the dye on for 20 to 45 minutes

How long to leave hair dye on grey roots

Why is there a difference of 20 to 45 minutes?

It all depends on the color you choose.

Before going into details, I’d like to highlight some aspects.

If this is the first time you dye your roots, leave the product for 45 minutes regardless of the color you use.

  • If you choose black 1, you should leave the dye on for 45 minutes.
  • If you use light brown, you should also leave it on for 45 minutes.
  • Finally, if you are coloring your roots for the first time with extra light blonde, you should also leave the dye for 45 minutes.

Alternatively, if you touch up your roots, the exposure time of the dye will depend on the color you choose.

Some colors have a stronger pigmentation and the roots absorb it more quickly.

In that case,  I advise you leave the dye on for 20 minutes. 

What are these colors?

  • Black 1
  • Dark brown 3
  • Brown 4
  • Light brown 5
  • Dark blonde 6

What about lighter colors?

In that case, even if you touch up your roots, you need to leave the dye on longer because lighter colors have weaker pigmentation.

Consequently, the roots will need more time to absorb the dye.

 If you are applying a light color, you should leave the dye on your roots for 45 minutes  to blend the colors between the growth and the rest of your hair.

What are these light colors?

  • Blonde 7
  • Light blonde 8
  • Very light blonde 9
  • Extra light platinum blonde 10

If you dye your roots with demipermanent dye, you should leave it on for 20 to 30 minutes

How long to leave hair dye on grey roots

The demipermanent dye is applied with a 9 or 10 volume developer and doesn’t contain ammonia. Therefore, you’ll need to renew the color more frequently.

Although most manufacturers recommend leaving it on the roots for 30 minutes, I recommend you consider the color you choose.

  • If you dye your roots black 1, dark brown 3, or brown 4,  leave it on for 20 minutes. 
  • If you dye your roots light brown or any shade of blonde,  leave it on for 30 minutes. 

If you dye your roots with a semi-permanent dye, leave it on for 20 minutes

How long to leave hair dye on grey roots

Semi-permanent hair color is not applied with a developer and doesn’t contain ammonia. So, it’s a gentle product that doesn’t penetrate the hair core.

It is deposited on the outside of the hair to form a film of color that fades with washing.

How long to leave it on?

  •  If you apply the same color you previously had,  leave it on your roots for 20 minutes.
  •  Alternatively, to apply a lighter color,  , leave it on for 30 minutes.

For example:

  • If your roots are brown 4, and you want to go for dark blonde 6, leave it on for 30 minutes.
  • If your roots are blonde 7, and you want to apply a very light blonde 9, leave it on for 30 minutes.

Finally, don’t overdo the exposure time of the semi-permanent hair dye on your roots.

Otherwise, you’ll only saturate your roots, and the color will fade faster with each wash.

Conclusions

The exposure time of the dye on your roots will depend on the color and the type of dye you use.

Remember that if you only want to touch up your roots, darker colors need more time than lighter colors due to the intensity of their pigmentation.

How long should you leave hair dye on GREY hair?

If you're touching up gray or white roots, you should let the color sit on your hair for 45 minutes. Gray hairs have no pigment, so they require the longest color processing times. For those with stubborn, color-resistant grays, a process called pre-pigmentation can be done within the same 45-minute period.

What happens if you leave root touch up on too long?

What happens if I leave Root Reboot on my hair for longer than the 10 minute processing time? If Root Reboot is left on hair for more than 10 minutes, the color will deposit more pigment and the shade may appear darker than the target shade.
Permanent dye contains strong chemicals, so you can easily land in trouble for forgetting to rinse in time. When the dye remains on hair for long, the dye absorbs moisture in the hair follicles, leaving your hair dry. Excessive hair dryness can make the hair break, especially if the strands are thin.

Why are my GREY roots not taking color?

According to hair biology experts and styling experts alike, grey hair is more resistant to color than younger hair because of its texture. The relative lack of natural oils in the hair compared to younger hair make it a rougher surface that tends to reject the color being applied, especially around the roots.