Setting the Tone
I am a self-admitted hair nerd who lives for the science behind hair color! If you've spent any time with me in person (or even read a couple blog posts), you'll likely end up with waaay more information about the why of hair science than you ever cared to.
Now that fall is here, I've been talking a lot about switching up hair color for the seasonal change...which also means I've been chatting about the different types of hair color and what they do and why the do what they do.
So why not write a little bit about those conversations and get the word out about the two different camps of traditional hair color: permanent and demi-permanent color.
Permanent Color
Permanent color serves only two distinct purposes, grey coverage and/or lifting & depositing color. It is highly alkaline, which means it swells the cuticle and can get pigment inside the hair shaft. When and why would a permanent color be selected for you?
You are battling a 30% or higher concentration of grey hair and. you. want. it. gone. As in completely covered, no trace of it anywhere. Permanent color will deposit the desired shade into those pesky silvers (as well as your naturally pigmented hair) and leave an opaque, uniform finish.
You are looking to go just 1-2 shades lighter OR you are wanting to shift the following color families: brunette to redhead, redhead to brunette, or a medium ash blonde to a lighter golden blonde. Permanent color also lifts/removes some the existing pigment in your hair and then deposits the shade you want.
One caveat: there is nothing permanent about permanent color. I know that sounds ridiculous, but all hair color fades! And. it. always. fades. warm. Regardless of who you are. The permanent aspect is that it permanently changes the structure of the hair. Because it has the capability to lift and deposit color, it will "unearth" the underlying natural warm pigment in your hair; that means gold for blondes, and copper for brunettes. Just know that as soon as you get into permanent hair color, this will likely happen to you down the road.
Demi-Permanent Color
Demi-permanent color only has the power to deposit pigment into hair that is darker than the shade you've selected. It's often very acidic (it shrinks down a swollen cuticle) sealing in color, smoothing the hair, and adds a reflective shine. Talk about a win-win!
Chances are, if you've ever had your hair colored by me, there's a 99% probability I've used demi-permanent color on you...even if you didn't know it. Read on to see what category you fall in to:
You've had highlights created by lightener. Bleach can only remove pigment, and hair either lifts with a red undertone or a yellow undertone -- you can't get around it, it's a human thing. Hairdressers will apply demi-permanent color (also known as toner or a gloss) to shift the hair to the desired shade of blonde. This is where we can make you "ash blonde," or "strawberry blonde," or "cornsilk."
You've wanted to transition from being a blonde to a redhead or a brunette. Going more than two shades darker from bleached hair requires the hair to be "filled" with the missing underlying red, copper, and/or gold pigments that have been previously removed. "Tint-backs" typically require at least two different chemical services during the appointment; one demi-permanent formula to fill the hair, and then a second formula that will get you the rest of the way to your goal shade.
You're coming in for a permanent color retouch for your roots. We use demi-permanent color on the length while your scalp is processing to refresh the color on your length and to make sure it matches the scalp.
You've asked for darker dimension/lowlights. Hairdressers need to be strategic about placing darker color formulas in the hair -- clients almost inevitably want to go lighter again at some point, and this way we don't need to use dynamite (aka super-strong bleach) to get clients blonde again.
You want grey-blending without the grow-out line. Some silver clients are great candidates for using demi-permanent as either a color melt/root smudge/solid color! If you're looking to "stain" just your grey hair (not opaquely cover it up) and and want a lower-maintenance retouch schedule, ask if this might be a good option for you.
But here's the deal with demi color: it lives just inside/under the cuticle, which means it's longevity isn't a great as a permanent color. Think of these two types of hair color as paint: permanent color is like wall paint (very opaque) and demi color is like looking through a stained glass window (translucent). It's sheer, and without the appropriate home care regimen (high-quality color-safe or toning shampoo, a fabulous heat protectant), you will literally be washing your color down the drain and/or vaporizing it out of your hair. Protect your investment -- I promise these products are totally worth it!
Now that you know more than you ever wanted to know about permanent vs demi-permanent color, do you have any questions I can answer for you? Do you think your hairdresser has ever used permanent color on you, or semi-permanent -- or maybe even both during the same hair appointment? Let me know what your guess, and I'll let you know if you're right! :)
