Pigmentation Hair color

Melanin Drying. One development (ca 1993) in hair coloring involves the formation of pigments within the hair that are very similar to natural melanin. Thus either catalytic or air oxidation of 5,6-dihydroxyindole [3131-52-0] can be effectively used to permanently dye hair within a short time (38). The formed color can, if required, be further modulated with dilute H2O2 or can be even totally removed from hair by this oxidant. 

In the United States the use of coal-tar dyes ia eye makeup is geaerally prohibited. The use of permanent and temporary hair colorants (Tables 16 and 17) and of organic dyes and their lakes is precluded. As a result, only iasoluble inorganic pigments can be used (Table 9). The sensitivity of the eye... 

Some types of paints and pigments that are used as facial make-up or hair coloring contain lead. Cosmetics that contain lead include surma and kohl, which are popular in certain Asian countries. Read the labels on hair coloring products, and keep hair dyes that contain lead acetate away from children. Do not allow children to touch hair that has been colored with lead-containing dyes or any surfaces that have come into contact with these dyes because lead compounds can rub off onto their hands and be transferred to their mouths. 

Cosmetic applications require specific effect pigments that are approved for use according to cosmetic regulations. The applications of these pigments include color cosmetics (lipsticks, eyeshadows, blushers, eye pencils, make-up, mascaras, nail lacquers), personal care products (shampoos, body washes, lotions, creams, oral care products, hair gels), and special effect items (theatrical and costume make-up, temporary hair color sprays) [5.164]. 

Cosmetics are natural or synthetic toiletry products that are used to maintain hygiene and include externally applied products used to enhance appearance. This class includes dental products, bath supplies (e.g., bubble baths, body washes, and bath beads), powders, lotions, lipsticks, perfumes, colognes, shampoos, depilatories, and hair coloring/waving products. Most of these products contain alcohols, aromatic hydrocarbons, perborates, and anionic and nonionic surfactants. Use of cosmetics is as old as civilization itself. Centuries ago wealthy women would apply the white lead pigment known as ceruse to their faces to appear fashionably pale - sometimes with lethal consequences. Women also used belladonna alkaloids like atropine to dilate pupils to enhance the attractiveness of the eyes in the late nineteenth century. 

Good thickener and viscosity builder. Effective wetting agent for pigments and dyes. Suitable for use in hair colorants, gels and permanent waves. 

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