(Vitually same as AATCC Test Method 23)
This method is intended for determining the resistance of the colour of textiles of all kinds and in all forms except loose fibres, when exposed to atmospheric oxides of nitrogen as derived from the combustion of butane (C.P.) gas.
This method may be used for rating colour fastness of dyes by applying the dye to textiles by a specified procedure and at a specified depth of colour and testing the dyed textiles.
A specimen of the textile and the test-control fabric are exposed simultaneously to oxides of nitrogen from burnt gas fumes until the test control shows a change in colour corresponding to that of the standard of fading. The change in colour of the specimen is assessed with the grey scale.If no colour change is observed in the specimen after one exposure period or cycle, exposure may be continued for either a specified number of periods or for the number of periods required to produce a specified amount of colour change in the specimen.
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