Bleaching your hair is a transformative process, capable of turning drab locks into vibrant, head-turning styles. However, it’s also a process that demands respect and understanding. Choosing the right developer volume is paramount, and the decision often comes down to 30 volume (30 vol) and 40 volume (40 vol) bleach. But what are the actual differences between these two strengths, and which one is right for your hair? This comprehensive guide will delve into the nuances, risks, and best practices associated with each, empowering you to make informed decisions for healthy, beautifully lightened hair.
Understanding Developer Volumes
Developer, also known as hydrogen peroxide, is the activating agent in hair bleach. It opens the hair cuticle, allowing the bleaching agent (usually ammonium persulfate or potassium persulfate) to penetrate and break down the melanin, which gives hair its natural color. The “volume” number indicates the concentration of hydrogen peroxide in the solution. A higher volume means a higher concentration, leading to a faster and more powerful lifting action. 30 vol developer contains approximately 9% hydrogen peroxide, while 40 vol developer contains around 12%.
The Role of Hydrogen Peroxide
Hydrogen peroxide is not just a bleaching agent in itself; it’s a catalyst. It creates an oxidation reaction that breaks down the melanin pigments within the hair shaft. This process is irreversible, which is why bleached hair remains lighter until new growth comes in or color is deposited back into the hair. The higher the concentration of hydrogen peroxide, the faster and more aggressively this oxidation process occurs.
Lifting Power Explained
The primary difference between 30 vol and 40 vol developer lies in their lifting power. 40 vol developer lifts hair color faster and to a greater degree than 30 vol developer. This means it can achieve a lighter result in a shorter amount of time. However, this increased power comes with increased risk of damage, especially if used incorrectly or on already compromised hair.
30 Vol Developer: A Gentle Approach
30 vol developer is often considered the safer option for several reasons. Its lower concentration of hydrogen peroxide makes it less aggressive on the hair, reducing the risk of damage and breakage. It’s a good choice for those with finer hair, sensitive scalps, or hair that has already been chemically treated.
Ideal Hair Types for 30 Vol
30 vol developer is generally recommended for:
- Fine to medium hair textures: The gentler action is less likely to cause breakage in finer hair strands.
- Slightly damaged hair: If your hair is already dry or has been previously colored, 30 vol can minimize further damage.
- Dark blonde to light brown hair: It can effectively lift these shades to a lighter blonde without excessive processing.
- Root touch-ups: When lightening regrowth, 30 vol can provide sufficient lift without overlapping onto previously lightened areas and causing damage.
When to Choose 30 Vol Developer
Consider using 30 vol developer when:
- You’re aiming for a subtle lightening effect.
- Your hair is already in a delicate condition.
- You have a sensitive scalp.
- You’re performing a root touch-up and want to minimize overlap.
- You’re using a bleach formula that is already potent.
Benefits of Using 30 Vol
- Reduced damage: Less harsh on the hair, minimizing breakage and split ends.
- Slower processing: Allows for more control over the lifting process, reducing the risk of over-processing.
- Gentle on the scalp: Less likely to cause irritation or burns.
- Suitable for sensitive hair types: Safer for fine, damaged, or previously treated hair.
40 Vol Developer: The High-Lift Option
40 vol developer is the powerhouse of hair lightening. Its high concentration of hydrogen peroxide delivers rapid and significant lifting, making it a popular choice for those seeking dramatic transformations. However, its potency demands careful handling and a thorough understanding of its potential risks.
Ideal Hair Types for 40 Vol
40 vol developer is typically reserved for:
- Thick, coarse hair: This type of hair can withstand the stronger lifting action without significant damage.
- Virgin hair: Hair that has never been chemically treated is generally more resilient and can handle the intensity of 40 vol.
- Dark brown to black hair: To achieve significant lightening, a higher volume developer is often necessary.
- Achieving platinum blonde: For lifting very dark hair to a very light blonde, 40 vol is often required, but always with caution.
When to Choose 40 Vol Developer
Opt for 40 vol developer when:
- You need to lift several levels of color.
- Your hair is naturally very dark.
- You have thick, healthy hair that can tolerate a stronger developer.
- You are experienced with bleaching and understand the risks involved.
Risks and Precautions with 40 Vol
Using 40 vol developer carries a higher risk of:
- Hair damage: Over-processing can lead to breakage, split ends, and a dry, brittle texture.
- Scalp irritation: The strong chemicals can cause burning, itching, and redness.
- Uneven lifting: If not applied evenly, the hair may lift at different rates, resulting in patchy color.
- Chemical burns: Prolonged contact with the scalp can cause chemical burns.
- Elasticity loss: High volume developers can significantly damage the hair’s elasticity, making it prone to snapping.
It’s crucial to perform a strand test before applying 40 vol developer to your entire head. This will allow you to assess how your hair reacts to the developer and adjust the processing time accordingly. Always follow the manufacturer’s instructions and never exceed the recommended processing time. If you experience any discomfort, such as burning or itching, rinse the bleach out immediately.
Comparing 30 Vol and 40 Vol: A Side-by-Side Look
To further clarify the differences, here’s a direct comparison of 30 vol and 40 vol developer:
| Feature | 30 Vol Developer | 40 Vol Developer |
|—|—|—|
| Hydrogen Peroxide Concentration | Approximately 9% | Approximately 12% |
| Lifting Power | Moderate | High |
| Processing Time | Longer | Shorter |
| Risk of Damage | Lower | Higher |
| Scalp Irritation | Less Likely | More Likely |
| Suitable for | Fine, damaged, or previously treated hair; lighter hair colors | Thick, healthy, virgin hair; darker hair colors |
| Ideal for | Subtle lightening, root touch-ups | Dramatic lightening, achieving platinum blonde |
This table summarizes the key distinctions, making it easier to weigh the pros and cons of each option based on your specific hair type and desired results.
Factors to Consider When Choosing
Beyond the basic differences, several factors should influence your decision between 30 vol and 40 vol developer. These include your hair’s condition, color history, and overall health.
Hair Condition
Assess the current state of your hair. Is it dry, brittle, or prone to breakage? If so, opt for 30 vol developer or even a lower volume (like 20 vol). Damaged hair is more vulnerable to the harsh effects of bleach, and using a gentler developer can help minimize further damage. If your hair is healthy and strong, you might be able to tolerate 40 vol developer, but still proceed with caution.
Hair Color History
Consider any previous chemical treatments your hair has undergone. Has it been colored, permed, or relaxed? Chemically treated hair is generally more porous and susceptible to damage. If your hair has a history of chemical treatments, it’s best to choose 30 vol developer to avoid over-processing.
Desired Result
What level of lightness are you trying to achieve? If you’re aiming for a subtle lightening effect, 30 vol developer is likely sufficient. However, if you want to lift several levels of color or achieve a platinum blonde look, 40 vol developer may be necessary. Be realistic about what your hair can handle and prioritize its health over achieving a specific shade in one session.
Strand Test
Before applying any bleach mixture to your entire head, always perform a strand test. This involves applying the bleach to a small, inconspicuous section of your hair to see how it reacts. The strand test will help you determine the appropriate processing time and whether the chosen developer volume is suitable for your hair.
Bleaching Best Practices
No matter which developer volume you choose, following proper bleaching techniques is essential for achieving optimal results and minimizing damage.
Protecting Your Skin
Always wear gloves when working with bleach to protect your skin from irritation and chemical burns. Apply a barrier cream, such as petroleum jelly, to your hairline and ears to prevent staining and irritation.
Mixing and Application
Mix the bleach powder and developer according to the manufacturer’s instructions. Use a non-metallic bowl and applicator brush. Apply the bleach evenly, starting at the roots (if you’re lightening virgin hair) or the darkest areas. Avoid overlapping onto previously lightened hair, as this can cause breakage.
Monitoring the Process
Check your hair frequently during the processing time. The lifting process can vary depending on your hair type and the strength of the developer. Keep a close eye on the color and rinse the bleach out as soon as you achieve the desired level of lightness. Never exceed the recommended processing time.
Post-Bleach Care
After bleaching, your hair will be more porous and vulnerable to damage. Use a moisturizing shampoo and conditioner specifically formulated for color-treated hair. Consider using a protein treatment to help strengthen and rebuild the hair shaft. Avoid heat styling as much as possible and use heat protectant products when you do. Deep conditioning treatments can help replenish moisture and restore your hair’s health.
When to Seek Professional Help
Bleaching your hair at home can be risky, especially when using higher volume developers. If you’re unsure about the process or have concerns about your hair’s condition, it’s always best to consult a professional hair stylist. They can assess your hair, recommend the appropriate developer volume, and perform the bleaching process safely and effectively. A professional can also correct any unevenness or damage that may occur during at-home bleaching.
Bleaching is a chemical process that alters the structure of your hair. When you are not fully confident in the process, the potential risks increase. Leaving it to the professionals could save you money and hair in the long run.
Understanding the differences between 30 vol and 40 vol developer is crucial for achieving your desired hair color while minimizing damage. 30 vol is generally safer for finer, damaged, or previously treated hair, while 40 vol is best suited for thick, healthy hair that needs significant lightening. Always consider your hair’s condition, color history, and desired results before making a decision. Prioritize hair health and consider a strand test before applying any bleach to your entire head. If in doubt, consult a professional stylist for expert advice and guidance. With careful planning and execution, you can achieve beautiful, lightened hair without compromising its health and integrity.
What is the main difference between 30 volume and 40 volume bleach developer?
The primary difference between 30 volume and 40 volume bleach developer lies in their strength, specifically the concentration of hydrogen peroxide. 30 volume developer contains 9% hydrogen peroxide, while 40 volume developer contains 12%. This higher concentration means that 40 volume developer will lift the hair color faster and to a greater degree compared to 30 volume.
Essentially, 40 volume developer pushes the bleach reaction further, leading to a more significant lightening effect in a shorter timeframe. However, this increased potency also comes with a higher risk of damage and potential for over-processing, especially for those with fine or previously lightened hair. The choice between the two depends heavily on the desired level of lift, the hair’s condition, and the colorist’s experience.
When should I use 30 volume bleach developer instead of 40 volume?
30 volume bleach developer is generally recommended when you need a more gradual and controlled lightening process. This is particularly beneficial for individuals with finer or more fragile hair, as it minimizes the risk of breakage and damage. It’s also a suitable choice when aiming for a lighter shade but not necessarily platinum blonde.
Additionally, 30 volume is often preferred for on-scalp applications, where the heat from the scalp can accelerate the bleaching process, making a gentler developer a safer option. If you are lifting previously colored hair or only need a few levels of lift, 30 volume can be sufficient and helps maintain the integrity of the hair. Consider using 30 volume if you are unsure about your hair’s reaction to bleach or if you are new to hair lightening.
What are the risks associated with using 40 volume bleach developer?
The most significant risk associated with using 40 volume bleach developer is the increased potential for hair damage. The higher concentration of hydrogen peroxide can weaken the hair’s protein structure, leading to breakage, dryness, and a loss of elasticity. Over-processing with 40 volume can result in gummy or mushy hair that is difficult to manage and prone to further damage.
Furthermore, using 40 volume developer increases the risk of chemical burns to the scalp, especially during on-scalp applications. This can cause irritation, redness, and even blistering. Due to these potential risks, 40 volume developer is generally recommended for experienced colorists who can carefully monitor the lightening process and assess the hair’s condition throughout.
Can I mix 30 volume and 40 volume bleach developer?
While technically you can mix 30 volume and 40 volume developers, it’s generally not recommended unless you have a strong understanding of hair chemistry and color theory. Mixing them creates a developer with a volume somewhere between 30 and 40, effectively diluting the strength of the 40 volume. This might seem like a good compromise, but it also introduces variables that can make the lightening process less predictable.
The resulting developer’s strength will depend on the exact proportions used, and it can be difficult to accurately determine the final volume level. This unpredictability can lead to uneven lifting or a less-than-desirable outcome. It’s generally better to stick to either 30 volume for a gentler lift or 40 volume for a faster, stronger lift, depending on your hair’s needs and your desired results.
How do I know which volume bleach developer is right for my hair?
Determining the appropriate volume of bleach developer for your hair requires careful assessment of several factors. Consider your hair’s current color, its overall health and condition, the desired level of lift, and your experience with hair lightening. If your hair is already light or fragile, a lower volume developer like 30 volume is typically the safer choice.
If you are aiming for a significant color change, such as going from dark brown to platinum blonde, and your hair is healthy and strong, 40 volume might be necessary. However, it’s always recommended to perform a strand test first to assess how your hair reacts to the bleach and developer. If you are unsure, consulting a professional colorist is the best way to ensure the desired results while minimizing the risk of damage.
What is a strand test, and why is it important before bleaching my hair?
A strand test is a crucial step before applying bleach to your entire head, as it allows you to preview the potential outcome and assess your hair’s reaction to the chemicals. It involves applying a small amount of the bleach mixture to a hidden section of your hair, typically at the nape of the neck, and observing the lightening process over a set period. This provides valuable information about how quickly your hair lifts and whether it experiences any adverse reactions, such as breakage or excessive dryness.
Performing a strand test is particularly important when using stronger developers like 40 volume, as it helps determine if your hair can withstand the chemical process without significant damage. It also allows you to adjust the bleach formula or processing time as needed to achieve your desired color while minimizing the risk of over-processing. Ultimately, a strand test is a simple yet effective way to protect your hair’s health and ensure a more predictable and successful lightening experience.
What should I do if my hair becomes damaged after bleaching?
If your hair becomes damaged after bleaching, immediate action is crucial to prevent further deterioration. The first step is to stop the bleaching process immediately, rinse the hair thoroughly with cool water, and apply a deep conditioning treatment or protein mask. Avoid using heat styling tools, such as hair dryers or flat irons, as they can further weaken the hair.
Focus on replenishing moisture and protein to rebuild the hair’s structure. Use gentle, sulfate-free shampoos and conditioners, and consider incorporating leave-in conditioners and hair oils into your routine. Regular deep conditioning treatments are essential for restoring elasticity and preventing breakage. If the damage is severe, consult a professional hairstylist for advice on restorative treatments or haircuts to remove severely damaged ends.