Hair Dyes are chemicals that are used to change hair color.

Consumers considering changing their hair color have a choice of coloring agents to use. What distinguishes them is how long they last and how they color hair. There are at least four basic categories of products:

Temporary hair colors are applied in the form of rinses, gels, mousses and sprays. These products merely sit on the surface of the hair and are washed out with the next shampoo.

Semi-permanent dyes penetrate into the hair shaft...