Nothing Lasts Forever: How Long Does Permanent Hair Color Last?

Despite the name, ‘permanent’ hair dye isn’t actually all that permanent. But before you go writing to the Better Business Bureau, understand that this isn’t fake advertising, at least, not really.

Permanent dye is the go-to choice for anyone looking to give their hair that perfect makeover. Whether it’s jet-black or blue, permanent dye can give your hair that missing ‘oomph’ you’ve been looking for. But wait, there are some things you should know about your favorite hair product:

How Do Permanent Dyes Work?

Unlike other dyes, permanent dyes don’t just coat your hair like paint; instead, permanent dye actually seeps into the hair, allowing the dye to change the color of the hair shaft from the inside out. The permanent dye does this with an activator, which opens up the hair cuticle and lets the dye’s pigments enter the hair.

Permanent dyes are best for grey hair, specifically because it changes/adds pigment to the hair rather than just coating it from the outside. Because the color comes from within the hair, permanent dyes last longer, are less prone to flaking, and are more natural-looking.

How Long Does Permanent Hair Dye Last?

Despite the name, permanent hair dye isn’t actually permanent. So, how long does permanent hair color last? Around 6 to 8 weeks, depending on the product and the application process. But here’s the thing: it can be shorter or longer, also depending on a number of factors.

You see, when salons or products say that their permanent dye stays in the hair for around 6 to 8 weeks, it means that your hair is most saturated with color within that time period. Beyond that, there will still be color, but, because of factors like exposure to heat and sunlight, it can be faded or flat. If you’re using a toner with high ammonia content, this could also speed up the oxidization of the pigment in the dye, leading to flat and dull colors after the 6 to 8 weeks stated on the box.

Remember: hair grows out (duh), and while this sounds like common sense, a lot of people who dye their hair tend to forget regrowth maintenance. If you’re not into roots, then it’s best to retouch it after the 6-week mark (also depends on how fast your hair grows).

Is There Permanent Dye in Rainbow Colors and/or Shades?

There’s a reason most vivid shades like blue, neon pink, green, and other ‘rainbow’ colors aren’t available in permanent dye form, and it has something to do with how colors work with each other.

Because permanent dye works by seeping into the cuticle, rainbow colors and shades will have to work together with your hair’s natural pigmentation. For rainbow colors and shades to work the way you want them to (i.e. vibrant but permanent), your hair’s cuticles must be devoid of pigment in the first place, otherwise, the dyes will be mixing or competing with your hair’s natural color (blue hair dye on brown hair will just end up looking like, well, a murky mess).

You could, however, remove pigmentation in your hair first by bleaching. However, adding colored dye into already bleached hair can severely damage your hair cuticles and shaft, which in turn, will lessen the efficacy of your hair dye. You could try to mixing the dyes (i.e. adding a neutral color to a non-neutral one), but this will, more often than not, result in a color that is dull and dirty.

Permanent hair dyes that come in vibrant, rainbow colors and shades isn’t currently available, and unless there are vast improvements in how pigments are mixed at a chemical level, don’t expect to see it in stores anytime soon.

Is the Boxed Permanent Hair Dye I Buy in Stores All That Different From What They Use at Expensive Salons?

Yes, they are quite different. Boxed dyes generally aren’t as strong, nor as long-lasting, as the ones they use in those expensive salons. That’s because salons usually tailor-fit the dyes they’ll be using depending on their customer’s hair type, hair color, dye preferences, and other factors. Most salons will have a professional colorist formulate a dye that they think will work best with your hair’s color, texture, and absorption capabilities.

Boxed permanent hair dyes, on the other hand, are commercially-formulated, so it won’t be an exact fit for your unique hair structure. Remember: you get what you pay for, so if you want permanent hair dye that lasts long and is vibrant, you’ll need to shell out the cash.

How Do I Maintain My Hair’s Color Using Permanent Hair Dye?

As with all things, commitment is key to maintaining the hair color that you want. But beware: coloring your hair is a chemical process, one that could damage your hair pretty badly if you don’t do it right. Apart from application, maintenance also involves controlling the kind of shampoo you use for your hair.

Most stylists will recommend that you use a non-detergent shampoo when washing your dyed hair, as there are less chemicals acting on the hair, thus reducing the risk of your artificial pigments washing out. It’s also best to avoid direct sunlight as much as possible, as these will quicken the oxidization of the ammonia in the dye, which in turn will speed up the degradation of the colors.

It’s also best to minimize the application of heat to your hair; this includes reducing the use of curling irons and hairdryers. Excessive heat damages your hair cuticles, which will allow the pigment in your permanent hair dye to dry up and flake out, giving your hair that mottled appearance.

In general, it’s best to go for a retouch of your permanent hair dye once you notice your roots growing out. But it won’t hurt to go before you start seeing some of your natural hair poke through; if, at any point, your hair isn’t the color or shade that you want, book a retouch asap.

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