ISO 105-E06:2006 specifies a method for determining the resistance of the colour of textiles of all kinds, and in all forms, to the action of dilute alkaline solutions.
Three tests differing in severity are provided. Any or all may be used, depending on the nature of the fibre.
Drops of a solution of sodium carbonate are placed on the specimen (textiles of all kinds and in all forms), the surface of which is rubbed gently with a glass rod to ensure penetration. The change in colour of the textile is assessed with the grey scale.
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