Surface Morphology Investigation of Tunisian Dromedary Hair

In raw materials of dromedary hair, there are two distinct fibre populations: The fine one is of textile relevance and the coarse one is rather worthless and must be as a rule separated prior to spinning and subsequent processing. The fibre surface morphology and fibre fineness of Tunisian dromedary hair has been investigated by means of scanning electron microscope (SEM). SEM microscopic method provides the fibre diameter, the scale shape, the scale frequency and scale height. The results show that dehaired dromedary fibre presents a relatively low mean fibre diameter (≈ 17 μm) with a high coefficient of variation (CV ≈ 25%). The scales of the dromedary fibre are on average extremely long and quite visible, they tend not to protrude from the fibre, appear almost convex, and provide a wavy appearance in profile of the relatively coarse fibre. On counting the scale frequency, that is, the number of scale margins within a determined fibre length of 100 μm on the surface of a fine (diameter 30 μm) dromedary fibre, comes out roughly five at eight and eight at twelve scale margins, respectively. The mean height of the cuticle scale is 0.12 μm and 0.24 μm, respectively, for fine and coarse dromedary fibre. These explain why dromedary fibres present a soft touch due to the prominence of the scale edges. This aspect of the surface structure has a high correlation with the felting capacity of the matter, and contributes to the concepts of handle and gloss.