Successful bleaching of pigmented fibres was, generally, evaluated by a maximum whiteness, a minimum yellowness, and less damage to the bleached fibers. A review of the literature reveals that many studies on pigmented fibre bleaching are concerned with improving the whiteness and mechanical properties of bleached fibres. In this study, we investigate the effects of the hydrogen peroxide concentration, bleaching time, and clarification bath on the bleaching efficiency of Tunisian dromedary hair. It was showed that 30？min bleaching time gives better result in term of whiteness. However, an increased bleaching time gives an excessive damage to the bleached fibers. Further, the damage incurred by the dromedary hair was more important than that for wool, as is shown by the tenacity results. We found that oxalic acid, which is used for rinsing dromedary hair (after bleaching), provides improved results in term of whiteness obtained with bleaching. Certainly, oxalic acid made it possible to remove the maximum of iron remaining on fibre after bleaching. Bleaching methods demonstrate the excessive damage incurred by the fibre when using hydrogen peroxide particularly with raise concentration. This damage leads to adverse effects on the tenacity fibre. 1. Introduction The unique aesthetic quality of pure wool has made it irreplaceable even in a market dominated by its inexpensive and abundantly available synthetic versions such as acrylics. Wool constitutes a minor segment (1.4%) of the total textile fibres produced globally [1]. However, a significant portion of the wool is consumed by the high-end fashion market because of its warmth, resiliency, and handle. Within animal hair fibres, specialty hair fibres are considered to be even more exquisite than sheep wool [2]. In particular, hair fibres are obtained from animals other than sheep, such as, mohair, alpaca, lama, and camel [3]. These fibres, mostly obtained from animals native to remote corners of the world, have a very small annual production, but capture the best markets in the high fashion industry [4, 5]. Therefore, in spite of a small quantitative contribution, the significance of wool and especially hair fibres in the apparel and textile industry cannot be underrated. In nature, animal fibres such as dromedary hair are usually found in various shades of brown or grey, due to the natural pigment, melanin. For light pastel shade textile articles, it is essential to use white material, and this can be obtained by the depigmentation of coloured fibres. Currently, the method of depigmentation commonly
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