Colour fastness of optionally aftertreated acid levelling and milling dyes on nylon 6.6 during washing in an activated oxygen-bleach containing detergent. Part 2: Correlation between the fading observed in the UK-TO test and after repeated domestic laundering

Part 1 of this study reported the fading observed when optionally after‐treated nylon 6.6, dyed with acid levelling and milling dyes, was subjected to both the UK‐TO test and multiple machine washing at different temperatures. The current study attempts to correlate the fading exhibited under the different test methodologies in an attempt to ensure that the UK‐TO test remains a reliable diagnostic test for the fading of ‘acid’ dyes on nylon 6.6 as a result of domestic laundering.