Today’s question comes from middle school student, Cassie, who is conducting research for her school science fair. Due to the age of this recipient I redacted any personal information that may identify her to the public.
My name is Cassie [redacted]. I am a student at [redacted]. For my science class we are required to do a science fair. I have always enjoyed doing my hair and others hair, so for my question I chose, ‘How does the amount of hydrogen peroxide used in a hair highlight treatment affect the final color of the hair?’ If you could answer that question for me I would be extremely grateful. Thanks for taking time out of your busy day to read this.
To answer your question, the amount of hydrogen peroxide (or developer as we refer to it in the salon) can vary depending on the lightener (bleach) you are using. Always check the mixing instructions on the bleach packaging.
Often times the ratio of bleach to hydrogen peroxide is 1:1, for example 1 ounce of bleach mixed with 1 ounce of hydrogen peroxide. However, like I said, this ratio varies.
For example, the bleach I like to use is called Goldwell Silk Lift High Performance Lightener. They are a German company and use the metric system in Europe. They instruct 35 ml (equal to approximately 1.2 ounces) mixed with one 25 gram scoop of their lightener (equal to about .882 ounces). As you can see with this company the mixing ratio is close to equal parts but not quite.
Although using the correct mixing ration is very important, it is also important to understand that there are 4 different levels of hydrogen peroxide. Hydrogen peroxide developers are oxidizing agents and are measured in volumes.
The volume refers to the amount of oxygen that would be removed from a peroxide solution if the molecules were broken into components.
In the United State we use four different Volumes: 10 volume, 20 volume, 30 volume and 40 volume. The higher the volume, the more lift you can achieve. Higher volumes are stronger and can be more damaging to the hair. It is also important to know that it is not advised to use higher than 20 volume on the scalp. Allowing 30 or 40 volume developers in contact with the skin can cause burns.
To understand the results of a highlight service you need to factor in the hair you are working on. When referring to the lightness or darkness of natural hair color we use a scale of 1 to 10 and refer to them as levels.
Level 1 is the darkest black. Level 10 is the lightest natural blond. An unnatural “bleach blonde” with the appearance of a white blond is described as a level 11 or 12.
Many bleaches claim they can achieve up to 7 levels of lift depending on the developer used.
10 volume (or lower) is usually used to deposit color on the hair without changing the level of lightness or darkness.
20 volume is used to lift 1-2 levels.
30 volume is used to lift 3-4 levels.
40 volume is used to lift 5-7 levels.
These are generalized results and some hair may be more or less resistant.
Here is an example:
Someone with black hair wants highlights. If lightener (bleach) is mixed with 40 volume developer (hydrogen peroxide). The results will be between a level 5-7. These will not result in a pretty blonde highlight. Most likely the bleach hair will look red or orange. If you are lucky to reach a level 7 it will still look very yellow. If this black haired client wanted red highlights, a second process involving the application of a level 5 or 6 red semi-permanent color could be applied to turn the highlights an even red tone.
Here is another example:
If a client with light brown hair, level 6, wanted light blonde highlights you could mix the bleach lightener with 30 volume developer to achieve a level 9-10 highlight.
Also know that hydrogen peroxide developers are not only mixed with bleach but also with permanent color, or tint as we refer to it in the salon. If a clients hair is what we call “virgin hair,” hair that has never been dyed or received any other chemical service, you can use permeant hair dye mixed with the proper suggested ratio of hydrogen peroxide to lift the hair as well. For example if the client with light brown hair, level 6, had never died her hair, she could achieve a blond highlight by mixing 30 volume hydrogen peroxide developer with a level 10 permanent hair dye.
I hope my explanations and examples have helped you to understand how hydrogen peroxide effects a highlight service. Formulating hair color is complicated and is dependent on many factors. Knowing all the factors and how they effect one another is very important and is exactly why hairstylists like myself must be properly trained and licensed to perform these services in salons.
I hope I helped you, Cassie! And if you have any other questions please feel free to email me again. Just wondering, when is your science fair? Is this a written report? Do you have to provide a visual? Maybe if you let me know what you are planning to present I may be able to make some suggestions
Ps. Sorry I practically wrote a book! There is a lot to know!