Black is the most resistant of all hair colors, and even residual amounts of dye can remain on the hair strand for months. Like any color, however, black dye can eventually fade and lose its luster, causing your hair to appear dull and lifeless. While black hair does not require as much maintenance as do lighter colors, such as pale blonde or red, there are certain beauty tips you can follow to keep your hair color as dark as possible.
Wash your hair under cold water, and use a gentle shampoo and conditioner. A shampoo designed specifically for color-treated hair is best, since these products typically contain color glazes. Baby shampoo, due to its delicate formula, is also an acceptable choice. Heat and harsh shampoos strip your hair not just of its dark color, but also of its natural oils. It's best to avoid hair products that contain many heavy duty detergents.
Wash your hair less. Even if you use top-of-the-line, color-safe shampoos, every washing will remove at least a little bit of black dye from your hair. If you have fine, oily hair, you may need to wash your hair more frequently than those who have a dry, coarse hair texture, but try to at least space out washings to every other day.
Avoid excessive sun exposure. Even short periods of casual sun exposure can cause your black hair to lighten. While some shampoos and hairsprays contain SPF, they are insufficient at properly protecting hair from the sun's UV rays. (See References 2) Instead, wear a hat or a cap if you intend to spend a lot of time outdoors.
Apply a gentle conditioner to your hair and wear a rubber cap when swimming in the pool or in the ocean. Chlorine and salt water strip the hair of its protective cuticle, causing color molecules to escape. (See References 3)