+22 How Long To Leave Demi-Permanent Hair Dye In References. But do the strand test first as perms can leave hair more porous and can allow color to absorb faster. Lighter shades may require longer processing or multiple applications.
Web it generally lasts through a few washes and can go even longer if you use the right products. Web the short answer is: 4 how long do i leave wella demi permanent hair color on for?
