While we wish the instructions were a bit clearer on how long to leave on the product ... t been impressed when using purple shampoos on her naturally red hair in the past, this colorist ...

"If you leave a purple shampoo on for too long, your hair will have a blue-purple tinge to it," Irwin cautions. Never exceed the specific product instructions and if you do choose to leave it on a ...

Color-depositing shampoos add specific pigments (either purple, blue or green) onto the hair shaft to maintain your desired color. Based on color theory, blondes should use purple shampoos ...