20 Volume Developer can lighten hair by itself, but it will take longer than if you use it with bleach. It can take up to an hour or more, depending on how dark your hair is. If your hair is very dark, you may want to try using 30 Volume Developer.
20 volume developer can lighten hair by itself, but it will take longer to see results than if you use it with bleach. It can be a good idea to test a small section of your hair first to see how your scalp and hair react to the chemicals.
Will 10 volume developer lighten hair by itself?
No, 10 volume developer will not lighten hair by itself. 10 volume developer is used to deposit color and is not used for lightening the hair.

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How long does it take 20 developer to lighten hair?
If you’re looking to lighten your hair, you may be wondering how long it will take. The answer depends on a few factors, including the type of developer you use and the current color of your hair.
20 volume developer will lighten your hair faster than 10 volume, but it is also more likely to cause damage.
If your hair is already light, it will take less time to lighten it further. If your hair is dark, it will take longer to lighten.
Generally speaking, it will take 20 minutes to an hour to lighten your hair with 20 volume developer.
However, this is just a general guideline – your mileage may vary depending on your individual circumstances.
Does developer permanently lighten hair?
No, developer does not permanently lighten hair. It is a common misconception that developer will lighten your hair permanently. This is not the case.
Developer is used in conjunction with bleach to lighten your hair. When used correctly, it will lighten your hair temporarily. It is important to note that developer should not be used alone, as it will not lighten your hair.
Does 20 Developer lighten hair with toner?
No, 20 Developer lighten hair does not contain toner. Toner is a product that is used to correct the color of your hair after it has been bleached or colored.
Will 20 volume developer lighten hair by itself?
Conclusion
No, 20 volume developer cannot lighten hair by itself. It is an oxidizing agent that must be mixed with a bleaching powder to work. When mixed together, they create a chemical reaction that breaks down the melanin in the hair, which lightens it.