Haraz Bark Powder Extract for Manufacture of


By S.B Ali, H.E Haroun, and A.E Musa.


The retannage process achieves a wide variety of purposes and is applicable to different kinds of chrome leather. The objectives of the process, to fill the looser and softer parts of leather in order to produce leathers of more uniform physical properties, to allow for the production of unlined footwear, to improve the chemical stability of the leather and to allow rapid finishing and delivery to the customer. Extract from the barks of Faidherbia albida (haraz), widely distributed in Sudan, and has been evaluated for its utilization in the retanning of the leather and presented in this paper. Barks of haraz have been extracted for 1 hour with distilled water (1:10 w/v) at temperature above 80˚C. The haraz extract prepared has been used for the retanning of wet blue leathers. The effectiveness of haraz extract in retanning of wet blue leathers has been compared with wattle retanning. The organoleptic properties of the leathers viz. softness, fullness, grain smoothness, grain tightness (break), general appearance, uniformity of dyeing of haraz retanned leather have been evaluated in comparison with wattle retanned leathers. Haraz retanning resulted in leathers with good grain tightness. Dyeing characteristics of haraz retanned leathers have been found to be better than wattle retanned leathers. Also physical strength characteristic and shrinkage temperature and were noted


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