This post is for people people who are starting with dyed hair. I don’t have much experience with bleaching out permanent dye products, and they do behave come out a lot harder than the semi-permanent dyes.
If you want to dye over another color, it will probably not be necessary to get all your hair white (again). If the old, faded color is close enough or contained in your desired new color, don’t bother bleaching it out. Just take into account the dye that is already in your hair when mixing/choosing a color.
My hair has been dyed so many times, this is the “completely bleached out” state.
What works? There will be variation depending on how bright and “pure” your desired color is, and how much already is in your hair. The lighter the color you’re starting with is, the easier is it to have it work with whatever you are putting on top of it. Also, with each dyeing step your hair can only get darker, so you can’t start with a hair color that is darker than what you want to get in the end. I’ve summarized this in the graphic below:
Click to enlarge the picture
On the left is the color you are starting with. The lighter it is, the easier it will be to make it work with your desired color. In the graphic, a check mark indicates that if your hair is faded enough, and you put the new color on top it should work. If a combination is crossed out, you probably need to bleach your hair to transition from your current color to the one you want. A question mark means that it can work, but it might not – depending on the exact shade/intensity you want to reach. Use your own judgement, as you probably know best which color(s) you want to end up with.
Getting rid of your old color
Be aware that even semi-permanent dye rarely washes out of your hair entirely. If you lightened your hair before the dye job, or if you have light hair, there will probably be color residue that will not go away by itself. Depending on how much dye you need to get out of your hair, you can either bleach it out, or try getting the job done without bleaching.
No bleach
A lot of the time it is enough to wash your hair several times so the dye fades enough to just put your new color on top of it. Try using anti-dandruff shampoo for this, as it draws a lot more dye out of your hair than regular shampoo does. This effect has to do with what it does to the scales around your hair, and how the scales enclose the dye pigments.
Bleach bath
In most cases, it will be the best (and less damaging) solution to do a bleach bath rather than full on bleaching your hair. Bleach bath here means using a mixture that is half bleach, and half shampoo on damp hair. The more shampoo you add, the more diluted the bleach will be. Adding the shampoo, and applying it to wet hair rather than dry not only makes this solution a lot easier on your hair, it also takes less time and effort to do it.
In this approach, after the old dye is out you can bleach your roots as usual.
Bleaching
I never had to bleach semi-permanent dye out with more than a bleach bath, but if you feel the need to just follow the directions in the bleach post. This is also how you can get rid of permanent dye, but be careful not to completely destroy your hair.
General rule: If you want to bleach dye out of your lengths, start with the lowest volume you can get away with, and leave it in as short as possible. Or go to a swimming pool. While this might sound like a joke, it is actually a great way of getting semi-permanent dye out of your hair. And it’s fun.
How to care for bleached hair?
As bleached hair is damaged already, it needs to be pampered – and that starts with the bleaching itself. I always try to make sure my hair is slightly greasy before bleaching. I only wash my hair twice a week, so I try to do all bleaching on the fourth day after washing. This really goes a long way towards keeping the scalp happy and healthy. Depending on your schedule, it might also help to do a very rich hair mask to prepare your hair for bleaching.
You will need to use conditioner on bleached hair, otherwise it will look like straw – and not in a good way. I usually use a rinse-out conditioner after shampooing, and depending on my hairstyle I apply leave-in conditioner or hair oil after towel drying my hair.
You also need to be gentle with bleached hair when it’s wet. I always thoroughly brush it before washing, and try to handle the wet hair as little as possible – at least before I add the leave-in oil/conditioner.
