Troubleshooting and practical problems

Reagent Acetyl acetone Acetyl acetone Chromotropic acid/HjSO, IN Na SOj + 0.05N iodine 

Sample preparation Over water in vapour atmosphere In water In water with wetting agent In buffer solution at pH 9.4 

Type 1 sample in the air above the water, type 2 sample in the water, EN ISO 14 184 part 1 = Japan Law 112, part 2 = AATCC 112. BS 6806 part 3 is a slight modification of AATCC 112. BS 6806 part 2 is called a free formaldehyde test method, but it also covers released formaldehyde, caused by elevated reaction temperature and the use of concentrated sulfuric acid for the colour development before colorimetrical determination. 

Chlorine retention is a special problem with amine and amide-containing finishes. When fabrics treated with these finishes are laundered with chlorine bleach, unsubstituted nitrogen atoms can react to form chloramines (Fig. 5.10). Chloramines hydrolyse to form hypochlorous acid that can decompose to materials that will degrade cellulose by significant strength loss and marked yellowing. DMDHEU products show less chlorine retention than do TMM or DMU products. Chlorine retention of A -methylol-based finishes is used for antimicrobial effects (Chapter 15.4 and Fig. 15.3 and 15.4). 

Cellulose fabrics can be treated with liquid ammonia to produce fabrics with 

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