Users of semi-permanent or temporary hair color can expect their color to last for about 6 weeks. Color fades with shampooing and exposure to air.
Demi permanent hair color can last up to 6 weeks and typically fades after 20 to 28 hair shampoo washes. As a hair-coloring agent, demi permanent formulas are used to enhance natural hair color, to darken the natural hair shade and to refresh previously colored hair.
Opinions on hair care products vary greatly from person to person, but the brands Wella, Matrix SoColor and Rusk are all highly regarded among professional hair stylists. Elgon is another hair color line that professionals rely upon for great quality.
A semi-permanent hair dye can last for approximately six weeks. The semi-permanent hair dye will fade progressively and through exposure to air as well as shampooing.
Vinegar does not strip hair color from the hair. Vinegar removes residue buildup on the hair without damaging it or the hair dye.
The curl from a permanent wave (or perm) can last as long as year, if it is done effectively. During this time, the perm may grow out and change a bit, but the curls will remain intact. Some perms may last only 3-6 months, depending on the type of perm that is performed...
Food coloring does not expire, nor does it lose its coloring power. Food coloring should be kept well-sealed to prevent contamination from dust or other particles.