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Materials
Markierter Test-Stoff Multifibre 6 (MF6) aus Versuch 1, TDK CD-R PEN, Infusionsflasche 50 mL, water, Heizquelle (siehe Brennstoffe und Brenner), scissors...
Experiment
1.  Take the six fabrics labeled 1 - 6 with a TDK CD-R PEN (Fig. 1).
2.  Transfer them into an infusion bottle with water to be heated (Fig. 2).
3.  Boil for 1 hour (Fig. 3), cut off the upper part of the MF6 (Fig. 4).
4.  Replace the water by fresh water and boil the lower part of the MF6 for another hour.
5.  Dry the MF6, fix the two parts of it on cardboard like seen in Fig. 4.
Observations
The water and 4 of the six fabrics are dyed redish, the water shows a fluorescent redish colour.
Explanation
The black colour contains a fluorescent redish substance that is soluble in water (siehe nächstes Experiment).
This substance is adsorbed by AC, Ny, PA and W but not by C and by PE.