Hair Coloring Tips: When we color hair in red tones with permanent hair color (permanent hair color is the most versatile and effective type of hair color) and no matter the tone you use – mahogany, chestnut, flaming red, auburn, etc. you’d expect such strong hair colors to last the longest. However, surprisingly they don’t and they fade faster than any other permanent hair color you use.
The reason for this is because red color molecules are smaller than any other hair color shade/tone molecules with which hair is colored. Red color molecules being smaller are washed out/fade faster from hair that is colored with a red tone even permanent hair color.
To refresh a red toned hair color you may use a semi-permanent type of hair color in between permanent hair coloring applications to intensify the color again. Since hair, which is colored with a permanent hair color is usually more porous, the semi-permanent hair color adheres well to this type of textured hair. Especially in the ends of the hair because they are usually the most porous part of the hair. (Make sure it’s really a “semi-permanent” hair color and not a demi-permanent hair color).
What is important to know is the more porous (dry/damaged) hair is the faster the color will fade. One of the reasons hair, which is colored with a permanent hair color becomes very porous, is because every time the permanent hair color is applied it is applied over the entire hair when the correct way is to only apply the color on the re-growth. This method makes the hair more and more porous.That is the major reason the color fades because the red color molecules literally fall out of the hair.
However since the red tones fade easily you basically have no choice but to apply the color through to the ends when the color needs to be applied again. There is a method you can use to mitigate the fading of the color and and not damage the hair as much when using permanent hair color and that is:
Mix more permanent hair color as usual, apply the color on the re-growth, process for 15 minutes (check the processing time of the hair color manufacturer). Don’t throw out what is left of your hair color mixture. After 15 minutes mix the remainder of the hair coloring mixture 
with a little bit of water and apply it to the rest of the hair bringing it through the ends and process it for another 15 minutes.
This hair coloring information will help you too when you color your hair at home. Check out the secrets of the New Home Hair Coloring System of The Right Hair Color for You.
Hair color manufacturers have introduced products that are supposed to prevent fading of red toned hair colors yet in my experience it has not made any difference.
