These are the primary colors.
Secondary colors are orange, green, and violet.
If you hair has a yellow tone, violet will cancel it out. When you chose a color in a swatch book, your hair may not come out that color because of the underlying pigment in your hair. Usually contain no ammonia and does not have a developer. Permanent - color formulas change the natural hair color. They require maintenance to new hair growth after 4 to 6 weeks.