Other Dyes for Hair

First shampoo the hair with a good cleaning shampoo. Rinse the hair thoroughly and towel dry. Thoroughly saturate the hair with the product, using plastic gloves if desired, being careful to minimize contact with the scalp. Dry the hair and style as desired. 

Salts of several metals including lead, silver, bismuth, cobalt, copper, iron, and mercury have been used in the past for dyeing hair [45]. Among these metallic dyes, lead dyes are the only ones in commercial use today. Lead dyes contain lead acetate and sulfur [46] (Table 6-12) and react with hair to darken slowly, presumably forming lead-sulfur complexes in the cuticle layers. These products are popular among men because of the slow gradual buildup of color however, shades are limited, and the dye can react if treated subsequently with bleaches, permanent waves, and even with certain other hair dyes [16], 

Dissolve the lead acetate in water by stirring. Disperse the sulfur in propylene glycol and add this dispersion to the lead acetate in water while stirring vigorously. Continue to stir while adding the fragrance and preservative dissolved in alcohol and the surfactant. 

Natural organic substances from plants are the earliest known hair dyes, but of the many substances of this type that have been tried over the years, only henna and camomile are currently used to a significant commercial extent [2], The active coloring material of henna (Lawsone) is 2-hydroxy- 

4-naphthaquinone. The structure of this active dye ingredient was established by Tommasi [51] and Cox [52], 

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