ISO 105-Z06:1998 pdf download – Textiles – Tests for colour fastness
1 Scope
This part of ISO 105 describes a method for assessing the migration propensity of a pad liquor system containing dyes or pigments, subsequently referred to as colorants, and which may also contain different types and amounts of migration inhibitors. The degree of migration is obtained by visual examination or by reflectance measurements. The test method may be used to compare the migration propensity of dyes and the effect on migration of different types of migration inhibitors, thickeners and electrolyte. The method may also be used to evaluate a pad liquor with which migration has been found on a continuous dye range.
2 Normative reference
The following standard contains provisions which, through reference in this text, constitutes provisions of this part of ISO 105. At the time of publication, the edition indicated was valid. All standards are subject to revision and parties to agreements based on this part of ISO 105 are encouraged to investigate the possibility of applying the most recent edition of the standard listed below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 105-A02: 1993, Textiles – Tests for colour fastness – Part A02 Grey scale for assessing change in colour.
3 Definitions
For the purposes of this part of ISO 105, the following definitions apply.
3.1 dye: Colorant applied to or formed on a substrate, via the molecularly dispersed state, which exhibits some degree of permanence.
3.2 migration: Movement of a chemical, dye or pigment between fibres, within a substrate or between substrates due to capillary forces.
NOTE — Migration may occur in textile processing, testing, storage and use.
3.3 pigment: Colorant in particulate form which is insoluble in a substrate, but which can be dispersed in the substrate to modify its colour.
3.4 pad: Impregnation of a substrate (usually fabric) with a liquor, followed by squeezing between rollers.
4 Principle
Fabric impregnated with test colorant alone, or with test colorant and migration inhibitor, is dried while partially covered with a watch glass, permitting differential drying and therefore, migration to occur. The degree of migration is evaluated by visual examination or by reflectance measurements of the covered and uncovered areas.
NOTES 1 When drying conditions are not constant and/or uniform, uneven migration may occur, causing shade variations during a run, or shade differences between the face and back, or between the side and centre of the fabric.
2 The pad liquor composition may be modified by varying the amount or type of migration inhibitor and tested in the laboratory prior to the application on the range. The colorant concentration, the fabric and the wet pickup should be the same in the laboratory as used on the range. It is then possible to correlate the test results with the improvement experienced in practice.
Immediately after padding place the fabric on a flat glass plate (5.4). Place the watch glass (5.5) on the fabric as shown in figure 1, and leave the fabric to dry at room temperature. Remove the watch glass and determine the degree of migration in accordance with clause 8 by comparing the dye concentration in the area of the fabric which was covered by the watch glass to the dye concentration in the area of the fabric which was not covered.