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How Long Can Hair Dye Last After Mixed

How Long Can Hair Dye Last After Mixed

Whether you want to take your hair game to the next level or simply want to save on salon bills, at-home hair coloring is a great option. It might be tempting to experiment and take your time when coloring your hair, but it can do more harm than good.

So, before you start coloring your hair, read our guide first so you’ll avoid hair disaster.

Whether it is your first time coloring your own hair or not, make sure you have enough time to apply the mix to your hair. Do you know that you cannot mix hair color formulas until you are ready to use them?

How Long Can Hair Dye Last After Mixed? The formulas in hair colors whether it is a permanent or semi-permanent cause the oxidation process, which is needed to penetrate the hair shaft. Unfortunately, once you have mixed the hair dye, it can only last up to 30 minutes. After half an hour has passed, the mixed hair dye won’t be effective and it should be tossed.

Why Does the Mixed Hair Dye Only Last Half an Hour?

For your hair dye to work, it needs to undergo a chemical reaction. Your hair dye contains aniline derivatives and alkalizing agent that reacts with developer or hydrogen peroxide, causing oxidation.

The oxidation process is needed for the hair color to penetrate your hair shaft. Basically, the peroxide chemically reacts with oxygen.

Unfortunately, the color mixture has a lifespan of half an hour whether you have applied the mix into your hair or not. Once you mixed the hair color and developer, you should use it within half an hour.

Using your mixed hair dye after an hour or 24 hours would only lead to hair disaster. If you think half an hour is not enough for dyeing your own hair, better seek help from professionals.

If you have shorter hair, only take the right amount of product that you’ll use to avoid waste. You can keep the unmixed product—the hair color and the developer—if you store them in their own containers.

If you store the unmixed product in airtight containers and at room temperature, it can last up to two months. If the product is completely unopened, it can last up to three years depending on its expiration date.

hair dye

What Does the Developer Do in the Hair Coloring Process?

The developer or the peroxide provides the chemical reaction in your hair dye, allowing it to penetrate into your hair shaft, and the color itself to develop.

Depending on the color of your hair dye, the developer can make the base color lighter or darker. Most of the time, it’s the strength of the peroxide that change the mixture.

You should choose developer strength depending on how many levels you need to lift. This is one of the things you should not experiment with unless you’re a pro. 

For standard hair coloring, mixing an equal amount of hair color and developer is ideal. If you mixed unequal amount, you’ll notice that the reaction of chemicals and color results are different.

For instance, using more developer than hair dye will only give you paler color results—it can lighten the color but won’t deposit enough dye into your hair.

On the other hand, using less developer will lessen the penetration of the dye into your hair shaft since the mixture isn’t enough to open the hair cuticle.

What You Should Know Before Coloring Your Hair

Read labels and follow instructions carefully.

When choosing an at-home hair coloring kit, don’t rely on the color on the box. According to experts, the developer in at-home permanent hair color is stronger than the ones stylists use at the salon. 

DIY projects might sound fun, but a hair disaster isn’t. Expiration dates and instructions are there for a reason, especially if you’re using a chemical-based hair dye.

Instead of taking some risks, save your hair from damage by following the procedure on your hair color kit. This is especially true if you use different brands of hair color as each product has its own specification.

Hair Dye with developer

Section your hair before preparing the mix.

Sectioning your hair, especially doing cap highlights, take some time. Since your mixed hair color only lasts for 30 minutes, it makes sense to section your hair first, so you’ll have enough time to apply the mix into your hair.

Once you’re all set, you can prepare the mixture and apply it to your dry, unwashed hair. 

If you’re just covering your gray hair, you can prepare half of the mixture and apply it to your roots. After the color is left for a few minutes, you can color your hair in the middle and ends as usual.

According to experts, it is better to apply the dye from the back going at the front to avoid patchy results.

Use all-plastic or all-wood everything, and skip metals. 

Do you know that metal can interfere with the oxidation process of your hair dye? In fact, metals—whether it is a spoon, hair clips, bowl, spatula, or palette—can cause the color to oxidize and even damage your hair.

This is especially true when mixing dyes and developer, so only opt for plastic spoons and wooden bowls.

How to Mix Hair Color and Developer

Remember, the ratio of hair dye and developer will have a huge impact on the hair color result. Depending on the hair color you want to achieve, you have to mix your dye and developer in different proportions.

While bleaching requires a higher volume of developer to remove the natural pigment from your hair, the lower volume of developer will only lift the hair cuticle for the dye to penetrate.

If you’re going for a drastic hair color change like from black to light blonde, you might need to use a greater amount of developer—but better leave it to professionals.

Professional stylists know how to assess your hair and the level that needs to be lifted. Also, they can determine the strength of developer that should be used, and they can assess if you need to pre-lighten your hair or not.

Professionals understand the lifting ability of developers better, along with its mixing ratio that will affect the final color result. If you simply want to add a tone to your hair but want to keep it at the same color level, you can use a lower volume of developer.

On the other hand, creating highlights will need a higher volume of developer, which can lift your hair up to four shades lighter.

Hair coloring is one of the most creative and exciting tasks to revamp your look. By heeding our guide, you’ll be able to make it right whether you’re a newbie or a pro.

Related Questions:

Can you use hair dye without a developer?

There are some hair dyes that can be used without a developer, but they won’t give you permanent results. If you want to try out hair trends for a short period of time, you may think of direct deposit dyes that are temporary and won’t require developer.

Think of pastel colors, rainbow shades, and jewel tones that can give you a one-of-a-kind look for special occasions. Unfortunately, these dyes can stain your hair and could make permanent hair color more challenging in the future.

What factors do professional stylists consider when selecting hair color?

Apart from your desired hair color, stylists can determine your natural hair color level, which is essential when lifting or coloring your hair. They also consider the state of your hair, along with the percentage of silver or grey hair, which can be color treated differently.

More than that, stylists consider your hair texture, density, and porosity since different hair types absorb color differently. Do you know that porous hair types need a lesser amount of developer? On the other hand, if the hair is coarse it needs to be softened before hair coloring for it to absorb the color.