The effect of urea on the alkaline and acidic hydrogen peroxide bleaching of wool has been investigated. There was an improvement in the whiteness of the wool or, alternatively, a considerable reduction in the bleaching time using a concentration of 100-200 g/l urea in the bleaching bath. No significant differences were observed at lower concentration of urea (less than 100 g/l) in the bleach bath. Alkali solubility of wool flannel increases with urea concentration during bleaching and often remains within tolerable limits.
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