Hair dyes semipermanent

Because most oxidation dyes contain three to seven components capable of acting as either dye precursors or dye couplers, and most contain p-phenylenediamine and resorcinol, several di-, tri-, and polynuclear colored species of this general type are formed in these reactions. 

Semipermanent hair dyes are generally applied to freshly shampooed hair and allowed to remain on the hair for approximately 20 minutes. The hair is then rinsed with water. Often a conditioner, packaged with the product, is applied, and the hair is rinsed again and then dried. 

The hair dyes of Table 6-8 generally consist of neutral aromatic amine, nitro aromatic amine, or anthraquinone derivatives. They are all highly polar ingredients and can be classified as mono-, di-, or trinuclear (ring) dyes. Wong [38] has studied the kinetics of dye removal from hair for this type of hair dye and concluded that under all conditions the larger, trinuclear dyes rinse more slowly from hair than the smaller, mononuclear dyes. 

For both bleached and unbleached hair, Wong [38] showed that dye rinse-out for small dye molecules (corresponding to the mononuclear species) of 

Wong [38] also found that the larger trinuclear dyes, analogous to those of Table 6-8, have a greater affinity for hair than the simple mononuclear dyes undoubtedly arising from a larger number of polar and Van der Waals binding sites between dye and hair. 

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Direct-reading analogue, 14 30-31 Direct Red 80, semipermanent hair dye,... 

Disperse anthraquinone dyes, 9 321-327 Disperse Blue 1, semipermanent hair dye, 7 857t... 

No embryotoxic or teratogenic effects were produced when pregnant rats were exposed by topical administration to their shaved skin of semipermanent hair-dye preparations containing 0.1-1.5% triethanolamine on gestational days 1, 4, 7, 10, 13, 16 and 19 (Burnett et al., 1976). [This study was not reviewed in detail by the Working... 

The principles of this study by Wong are being utilized today in semipermanent hair dye products in the following manner. It is well known that diffusion into and removal of dye are faster in weathered tip ends than in the root ends of hair [5]. Thus, blends of dyes are used not only to obtain the right blend at root and tip but also to provide a more even wash fastness in both root and tip ends of hair. For example, blends of single ring dyes diffuse more readily into and are retained more readily in root ends, whereas blends of dinuclear and trinuclear dyes are retained more readily in tip ends [40]. Thus, the proper blending of mononuclear and dinuclear with trinuclear dyes will provide a more even wash fastness to both root and tip areas of hair. 

There are three basic steps to the usage instructions for semipermanent hair dyes first, the allergy test second, the strand test (both are described under... 

The sensitization symptoms from oxidation dyes are a discrete dermatitis at the periphery of the scalp and on the edges of the ears and itching scalp occasionally, eruptions occur on the face, especially around the eyelids [62, 63], Eruptions on the trunk and limbs are rare [62], Usually symptoms appear several hours after the dyeing process.Treatment of this allergic reaction consists of oxidation of residual paradiamine with peroxide in saline solution and application of corticoid creams or lotions [63]. Allergic reaction to hair color rinses is rare [58] however, a few incidents of allergic reaction to semipermanent hair dyes have been reported [59]. 

Uses Colorant in semipermanent hair dyes mfg. of mordant dyes for leather, nylon, silk, wool, and fur... 

This azoic coloring can be reduced in paraphenylene-diamine (PPD). It can be found in some semipermanent hair dyes, and patch tests are frequently positive (about 30%) in hairdressers with hand dermatitis. Because of cross-sensitivity, the detection of sensitization to p-aminoazobenzene may be assumed by a PPD test. 

Disperse yellow 3 is an azoic dye responsible for occupational contact dermatitis in workers in the textile industry. It can be found in some semipermanent hair dyes. 

Figure 7.1.5 Positive-ion FAB mass spectrum of semipermanent hair dye containing polyethoxylated (n=3-14) oleyl (A)/linoleyl (B)/ricinoleyl (C)methylammonium chloride. Adapted from Maffei Facino et al (1997) with permission.

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