Disperse dyeing of nylon 6 fiber using gemini surfactants containing ammonium cations as auxiliaries

Nylon 6,6 knitted fabric was dyed using three, levelling dyes and three milling dyes and the dyeings were aftertreated with a commercial syntan as well as a newly developed full backtan. When the dyed samples were subjected to five, consecutive ISO 105:C06/C2 wash tests, it was found that while the syntan was effective in improving wash fastness, the new backtanning process imparted greatest wash fastness improvement.