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Whether you are a compulsive hair dyer like me or you just bleached your hair once and now are trying to dye it back to a darker color, you may find that your hair has reached a point that it just won't hold color anymore. Even if you put a nice dark hair dye over the top of your hair within no time it will wash out to a faded mousy brown color that just isn't very pretty. If this sounds like you it is likely that you have damaged your hair shaft so that the color molecules just wash away rather than getting trapped inside.
Head down to your local beauty supply store and pick up something called protein filler. They sell protein fillers in various shades like black, red and brown, but personally I always just choose to buy neutral protein filler, which is clear. A large sized bottle of neutral protein filler costs around $5.00 and will make all the difference in the world with how your dye job comes out.
Next, pick up a box of hair dye in the color you want for you hair. Get everything ready like you are going to dye your hair like normal. Start by getting your hair damp and then saturate it with the protein filler. Make sure to hit all of your strands and not miss any spots in the back. Once you have the protein filler on your hair you will need to let it set for 20 minutes.
After 20 minutes you are ready to dye your hair. DO NOT rinse the protein filler out of your hair before dying it. Just apply the hair dye like normal right over the top of the protein filler and follow the timing instructions on the box of hair dye for how long to leave it in. When the time is up rinse your hair thoroughly and condition it using the conditioner that came with your hair dye.
Protein filler works to help seal the color into your hair shaft so it will last longer. Not only that, but it helps the color go on more evenly so you don't have spots that are darker or lighter and it helps to repair the damage to your hair at the same time. What more could you want?
While your hair dye may not last as long as if you had applied it to virgin hair, it will last much longer than it would without using the protein filler and can help make it possible to go from a very light color to a very dark color easily. Apply any leftover protein filler to your hair periodically to help condition your hair and keep it in great shape. All in all it is an excellent product and well worth buying for great hair dying results.