Improvement in the dyeability of viscose

• Published in: Coloration technology Vol. 125; no. 5; pp. 262 - 268
• Main Author: Chattopadhyay, D P
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.10.2009
• ISSN: 1472-3581; 1478-4408
• DOI: 10.1111/j.1478-4408.2009.00205.x

The effect of alkaline pretreatment with sodium hydroxide and sodium zincate on the dyeability of viscose has been studied. Both agents could enhance the dye accessibility to viscose, but sodium hydroxide was found to be more effective compared with sodium zincate. The maximum exhaustion of different reactive dyes was found with 7.5% w/v sodium hydroxide pretreated samples. Both the rate of dyeing and final dyebath exhaustion of viscose was significantly improved after such pretreatment. The pretreatment could also effectively replace the electrolyte requirement for some reactive dyes. The alkaline pretreatment also generated higher colour depth on the printed fabric. The change in surface morphology of the fibre as a result of sodium hydroxide treatment was examined through scanning electron microphotography. The weight loss as a result of this treatment was critically studied. 10% w/v sodium hydroxide was found to cause maximum loss in weight of the viscose fibre.