Bleach, peroxide and developer are the unsung heroes of the hair colouring world, working in tandem to lift, lighten, and deposit colour with precision. There can, however, sometimes be some confusion between the three.

People often get mixed up with bleach, peroxide, and developer due to overlapping terminology, their roles in the hair colouring process being connected, and people not really knowing what each one does.

In this guide, we aim to provide you with a clear and comprehensive guide on the specific roles of bleach, peroxide and developer.

Let’s get into it… 👇🏻

Peroxide vs. Bleach vs. Developer

Even the most experienced hairdresser may need to brush up on the scientific differences between the big three. And that’s why, in this article, we’ll dive deeper into the use cases, similarities and differences between bleach, peroxide, and colour developers.

It all starts with one common ingredient – Hydrogen Peroxide

Bleach and developer work together to lighten hair, and they both contain hydrogen peroxide. Since it is a key ingredient in both of these products, people might use the terms “peroxide” or “developer” to refer to the entire lightening or colouring process.

Some hair care products might also use different terms on their packaging, contributing to confusion. For example, a product might be labelled as a “bleach kit” or a “developer kit.”

Let’s take a look at each component in more detail…

What is Hair Bleach?

Hair bleach is a chemical product used to lighten the natural colour of hair. It is a powerful agent that works by oxidizing the melanin, which is the pigment responsible for hair colour, in the hair shaft.

Bleaching is a popular method for achieving a variety of hair colour effects, from subtle highlights to dramatic transformations.



Hair Bleach – What you need to know

The primary active ingredient in hair bleach is hydrogen peroxide.

Now for the sciency bit. 🧪

When applied to the hair, hydrogen peroxide breaks down into water and oxygen, releasing oxygen molecules that penetrate the hair shaft.

As these oxygen molecules interact with the melanin in the hair, they break down the pigment, causing the hair to lighten.

You can use different volumes of developer (a cream or liquid that activates the bleach) to achieve specific levels of lift.

While bleach can be a powerful tool for achieving a desired look, it’s crucial to follow proper application guidelines and take precautions to minimise damage to your client’s hair. Over-bleaching or using inappropriate techniques, such as overlapping bleach, can lead to dryness, breakage, and overall damage to the hair structure.

What is a Hair Developer?

Also known as a developer solution or peroxide developer, this chemical product is used in conjunction with hair dye or bleach to achieve the desired colour or lightening effect.

The developer’s primary function is to activate the colour molecules in the hair dye or assist in the oxidation process of bleach, facilitating the chemical reaction that alters the colour of the hair.

Developer – What you need to know

The key ingredient in most hair developers is hydrogen peroxide (H2O2). The concentration of hydrogen peroxide in the developer can vary, and different volumes are available to achieve various levels of lift or colour intensity. The volumes typically range from 10 to 40, with ten being the least aggressive and 40 being the most potent.

Here’s a general breakdown of developer volumes and their uses:

  1. 10 Volume (3%): Used for depositing colour without lifting the natural hair colour. This volume is suitable for toning or darkening.
  2. 20 Volume (6%): Provides moderate lift and is commonly used for covering grey hair or lightening natural hair colour by one to two shades.
  3. 30 Volume (9%): Offers significant lift and is suitable for lightening natural hair colour by two to three shades. It is often used in more substantial colour changes.
  4. 40 Volume (12%): Provides maximum lift and is used for significant lighting. It is typically used with high-lift hair colour or bleach for dramatic colour changes.

It’s crucial to choose the appropriate developer volume based on your client’s desired hair colour outcome and the condition of their hair.

Higher volume developers can be more damaging to the hair, so it’s important to follow the instructions provided with the hair dye or bleach product. Additionally, using a quality conditioner or treatment such as OLAPLEX after the colouring process can help maintain the health and integrity of the hair.



What is Peroxide?

As mentioned above, Peroxide is a common ingredient in both developer and bleach, contributing to the oxidative processes that lightens or changes the hair colour.

Peroxide is a chemical compound that contains the peroxide ion (O2^2-). The most common type of peroxide is hydrogen peroxide (H2O2). Hydrogen peroxide is a clear and colourless liquid that is widely used for various purposes, not just in the hairdressing industry.

Peroxide – What you need to know

Hydrogen peroxide is often mixed with other chemicals, such as ammonia, to form a hair bleach or hair colour developer. In this capacity, it serves to lighten the natural colour of hair or to activate the colour molecules in hair dye.

Peroxide or ‘Hydrogen Peroxide’ is simply just the chemical component found in both bleach and developer to help lighten hair.

Understanding the distinct use cases of peroxide in developer and bleach is essential for achieving your clients desired hair colour outcomes while maintaining the health and integrity of their hair. And as is always the case before undertaking any bleach or colour services – Don’t forget the importance of patch testing!

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