Hi there
In our salon we would use Tigi Dumb Blonde Recontructor for hair of this type.
This is the link to it:
http://www.the-salon.net/shop/product.php?categoryid=0&brandid=2&typeid=3&productid=78#displayproduct
Once a week we would recommend that you apply the Recontructor to your hair and then wrap a warm towel around your head and leave for as long a possible.
This will rejuvenate your colour and add protein and moisture to your hair which your maybe lacking due to the chemical process.
I use this myself and it is very effective
Thanks
Claire
www.the-salon.net