Introduction: Hair Dye Science

About: I'm an animation director by day and Queen of the monsters by night. I picked up most of my costume and prop building skills through hands on experimentation with materials. Experimentation led to addiction,…

Understanding the science of what is physically and chemically happening to your hair throughout the dying and aftercare process will give you insight into how to get the most mileage out of your color while maintaining truly healthy hair. We've all seen beauty product buzzwords like "sulfate free", "lifting" and "hydrating", but what does it all mean, and does it matter if all I want is bright color??

In this Ible, I've used a combination of photos and simple illustrations to explain the need-to-know science behind hair dye, as well as tips for keeping your hair healthy and your color vibrant over the course of time. This information is based on research and experience over 16 years of hair dying, as well as input from my color savvy hair dresser.

Step 1: How It Works

Each of your hair is covered in ridges, a structure referred to as the cuticle.Think of these like scales on a dragon or the points on a pinecone.

Healthy, natural hair is pretty smooth, with these cuticle ridges lying down flat and slick.

So how do we get dye to stick to this smooth surface? Much like a woodshop project, you'll need to rough it up to create a surface the dye molecules can stick to/ lodge under. The sand paper in this analogy is the main chemical in most permanent hair dye; Ammonia.

Ammonia opens the cuticle, lifting those ridges up as if they've been brushed the wrong direction. This allows chemical processes to go to work on the core, or "cortex", of the hair.

Ammonia can also be very damaging to your hair structure if used frequently!While sometimes a necessary evil to achieve the results you want, it pays to be smart about your exposure and finding alternatives. More on this later...

If using a permanent dye, your process will involve a Developer.The function of the developer is to "lift" (remove) your hair's natural pigment so that it can be more easily replaced by a lighter shade.

Developers come in different levels. The more dramatic your color change is, the higher your developer number will be.

Someone looking to match their current color or go darker will only need a developer level of 10, since you don't really need to 'lift" out your current pigment.

Someone looking for subtle change (going dark blonde to light blonde) will only need a lift of 20.

A deep brunette going blonde may need a lift of 30 or 40 to make the full transition, and then possibly a color toner after that. Ever see someone with orange hair that doesn't look like they meant to do that? Chances are that was a home attempt at brunette-to-blonde. I highly recommend at least consulting with your hairdresser before leaping the color spectrum. A professional can give you sound advice on how to get the best results with the least damage.

After the developer has done its work, Color Molecules cling under those lifted ridges, bonding to the hair and changing the appearance.


Semi-Permanent dyes work a bit differently. Because they don't contain ammonia and most don't require developer, they don't do any "lifting" or raise the cuticle much. This is why the side of a semi permanent hair dye box will likely advise you to stick within 2 shades of your natural color --going much farther simply won't happen. Semi-perm dye molecules stick to the outside of your hair shaft, forming a tinted layer.Pro: less damaging for your hair since it doesn't get roughed up. Con: The dye has less staying power because it's just sitting on the surface.

Most semi-permanent dyes advertise a gradual fade out over 28days, the benefit being no hard line as your roots grow in. Many fade faster than that due to environmental factors or bad hair habits.I'm a big advocate of semi-perm dyes because they're much kinder to your hair. I currently use permanent dye only once or twice a year to help chemically straighten my grays, but maintain vibrant color year round exclusively using semi-perms like Ion Color Brilliance and Special Effects.

Step 2: Sealing It In

Most box hair color comes with a tube of aftercare conditioner that claims to nourish hair for shine and softness.

While these conditioners are rarely as natural and fruit oil derived as some brands might claim, they do serve an important role in the dying process.

To get those dye molecules to lock in place, the cuticle ridges must be resealed (smoothed) down again. Conditioners help achieve that. Your hair feels good and looks shiny because the ridges are all smoothed out and going in the right direction again.

Keeping your hair moisturized keeps that cuticle sealed, thus the hair retains the dye longer. It is a good idea to condition any time you wash your hair and deep condition once a week, paying special attention to the last 1-3 inches at your ends where breakage and dryness is most likely to occur.

Store bough brands I have found to be very vibrant color-friendly include Mane n' Tail conditioner and L'Oreal EverSleek Reparative Conditoner.

Vinegar Rinse --Another great way to seal the cuticle and promote shiny hair. Apple cider vinegar and white vinegar both work. This is a favorite conditioning method of folks who are trying to steer away from chemicals in their beauty regime. You can do a vinegar rinse as part of your initial dye rinse-out, or keep some on hand for weekly use.

Simply mix 2 Tbsp vinegar in 1 cup water and keep it in a bottle in your shower. Avoid contact with eyes, and remember to dilute with water or you'll smell like salad dressing!

Step 3: Temperature

Hot and cold play roles in the science of hair dye as well.

Heat opens up the cuticle, much in the same way ammonia does chemically. This is why some hair dyes will suggest covering your head or applying heat while the color sets. The extra heat, whether from your own head or an external source like a blow dryer or steamer, optimizes the dye's processing for stronger results. The hair opens up, allowing color and moisture to really get in there deep.

Temperature's effect on hair is also why you might want to avoid extremely hot showers if you want to keep your color. Heat will open the hair up and allow dye molecules to escape easier.

Conversely, cold water helps seal the cuticle. Many hardcore dyers suggest only cold water rinses for your hair, which also promotes shine.

Step 4: All Natural Hair Treatments

While chemicals are a nearly inevitable part of hair dye (with the exception of henna), there are all natural ways to keep your hair balanced and able to support coloring.Hydration is a key factor.

Olive Oil --I apply a light coating of olive oil to the ends of my hair most nights before bed. This gives the oil all night to sink into the hair and moisturize, helping prevent dryness and breakage caused by frequent coloring. It washes out with my morning shower so there's no trace of greasiness by the time I'm in public.

To avoid going overboard with the oil, I put some in a spritz bottle (along with a few drops of peppermint essential oil for scent). To apply, I spritz oil twice into my palm, then work that amount through my ends. Your hair will become shiny and slightly textured, but you shouldn't be so oily that you'll leave a grease spot on your pillowcase.

Coconut Oil or Honey Hair Masks -- Both are popular ingredients for deep conditioning hair masks, but I have only tried coconut oil. Be VERY sparing! If you're only applying to your ends, a coin size amount of coconut oil will do. Avoid application to the scalp until you are well acquainted with washing/ rinsing out the oil. It can take a little work and some shampoos are more effective at cutting the dense oil than others. I highly recommend doing your first coconut conditioning experiment on a weekend when you don't have anywhere to be. You may need a little extra time to perfect your gunk removal strategy.

Step 5: Fight the Fade!

While some loss of vibrance is reasonable to expect over time, if you're experiencing major fade out very quickly then there is probably a scientific culprit working against your dye.

Color Choice -- The major villain in my story is the red dye molecule itself. Red dye molecules are the largest, making it difficult for them to fit under the ridges of your lifted cuticle. They can cram in there, but it's sort of like putting on a pair of pants that is a size too small; you'll want to get out as soon as you can. If the hair cuticle does not get sealed and stay sealed, big fat red dye molecules basically just fall out of the ridges any time you wash.

Damaged Hair -- Hair that is too dry and damaged will not retain dye as long as healthy hair. Damage is typically a result of your daily habits and can be corrected once you identify what it is you're doing that is harmful. damage also results in a loss of moisture, which compounds poor hair condition and color loss. See photos for my shameful mistakes.

Damage from Over-Processing --I went through a period where I was using harsh drugstore box dyes every 3 weeks or so, trying to maintain super bright color. What I didn't realize was the reason my hair wasn't able to hold color anymore was BECAUSE I was dying too often. The ammonia had roughed up my hair so much that the cuticle could no longer be conditioned smooth again. Color molecules and moisture had no means of locking in, and would be washed away very quickly. This resulted in cutting off about 5 inches of super crispy hair and a moratorium on drugstore dyes for over a year to grow it back. Staying away from ammonia for a while helped my hair regain health and the ability to retain color more effectively.

Damage from Heat Styling-- Heat styling is drying by nature, but using tools that are kinder to your hair can prevent tons of damage. If you straighten your hair daily like I do, look into ditching your flat iron for a hot brush. Flat irons (even those that claim to infuse moisture or glide smoothly) are still essentially raking down the hair shaft. You're at high risk for damaging the hair's structure and gradually stripping out color. A year of flat ironing left me with raggedy, dry ends. Switching to a hot brush (John Freida makes a pretty affordable drugstore model) not only proved to be more effective for straightening, my hair is much healthier and color stays in longer.

Damage from Products -- You've probably heard the term "sulfate free" in relation to hair care, but may not know what it means. In short, sulfates are the chemicals in soaps and detergents that make them lather up into fun, picturesque bubbles. Sulfates are intended to cut through grease, whether that be on your dishes or on your head. In doing so, they can be a too bit harsh on your hair, causing dryness and damage to the cuticle. As you now know, this leads to loss of color. Consider trying a sulfate free shampoo or conditioner and see if it makes a difference in your hair health and color retention. I also suggest using color/ heat protectant if you heat style frequently.

High Chlorine Water -- In the U.S., all tap water has some degree of chlorination. Most of us don't think about it because it isn't really enough to taste or smell, but it is there, and it can add up when it comes to hair color. Do you find that your hair color fades very quickly, especially on the back of your head (where the shower water probably hits you if you're turned away to not get soap in your eyes)? Your color might be suffering because of daily exposure to higher than expected doses of chlorine. There are a few things you can do about this:

Test Your Water--If you want to be sure, you can test your water. There are a variety of home chlorine test kit options available on the market. If you're an aquarium hobbyist, you probably already have some water quality test strips that will measure chlorine, among other things.

Get a Filtered Shower Head -- I ended up doing this when I discovered our current apartment's water was SUPER chlorinated. A filtered shower head will take care of chlorine and other impurities before they reach your hair. These are also recommended if you find you have dry, itchy skin, which may also be a symptom of too much chlorine exposure. There are a number of affordable options out there and I found it easy to install and change filters.

Limit Your Exposure -- Plain and simple. If you think your shower water might be to blame for dry and faded locks, keep your head out of the water unless you're actively washing it. Lean out of the stream for your other lathering, leg shaving, etc. Deep condition to restore hair health and see if less time in chemical laden water makes a difference for you.

Step 6: Color Depositing Conditioner

My favorite way to fight the fade is to use a custom color depositing conditioner at least twice a week.This keeps your color looking fresh and eliminates the need to dye so frequently.You can also use it to give a boost of color in a selected area of your hair. I sometimes apply a different color of conditioner to my ends for a faux dip-dye look. This was Ion Color Brilliance Fuchsia on top of a more natural auburn base.

Below is my simple recipe for vibrant reds. Explore the semi-perm cream colors at your local beauty supply store. Any dye that does not require a developer can be used to create your own shade of color depositing conditioner.

You Will Need....

Semi permanent hair color of your choice (does not require a developer)

Conditioner (big cheap bottles work great for this)

Re-sealable plastic tub

Instrument for stirring (tint brush, plastic spoon, etc)

Find a plastic container. Make sure it is easy to use and cleansed of its previous contents.

Squeeze in the amount of hair color you would normally use for one full head dye application. In my case this is 1/2 tube Ion Color Brilliance red and 1/2 tube magenta. Cover with a very generous amount of your cheap conditioner. You want a 3:1 ratio of conditioner to color. This filled my tub a little over half way.

Mix until creamy and color is consistent throughout. The color will appear just slightly diluted due to all the extra conditioner stretching out the dye. *Bonus: Add a few drops of peppermint essential oil to the cream for some extra wake up zing in the morning. This is just an option if you like the smell. It will not affect the function of the conditioner at all.

Seal container and place in the shower for easy use every other day. Apply a palm full to your scalp/ bans and another palm full to your ends. If you have longhair, you will get a more even distribution by loosely splitting your hair into pigtails and applying a portion to each half of your ends.

Be mindful to spread it all around with you hands, working it through the hair evenly. If you tend to slap it on your head in the same place every day, you'll end up with some places that are noticeable brighter than others (I made this mistake in middle school and earned the nickname "Spot"). Gloves are not needed unless you prefer it. The color conditioner may stain your hands immediately after use, but it will go away by the time you're finished with your shower.

Try to leave the conditioner on for at least 2-3 minutes. Hold your head out of the water while you scrub your face or shave your legs to give the color conditioner time to deposit pigment. Rise and dry as usual.

Using this color depositing conditioner over the course of a month extends your dye job and eliminates the need to use harsh chemicals on the hair so frequently. I have effectively cut my hair dying in half this year, which makes for much happier hair.

Step 7: Rock Out With Your Color Out

With the science of hair dye under your belt, keeping your 'do looking great is well within your grasp. I hope this write up has helped you identify some solutions for your current color needs and advised you on how to keep your hair ever healthy, whatever the shade!

If you enjoyed this Ible, consider sending a vote in the Dying for Color contest. Feel free to post your hair dye victories and fails in the comments below.

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