Acid tendering of sulphur black dyed textiles
Sulphur blacks are the most important dyes for cotton, with which are cheapness, remarkable fastness to light, washing. However, its great disadvantage is simultaneous oxidation of the sulphur split off to sulphuric acid during storage in a hot or humid atmosphere. It turns attacks the cotton and weakens it, This so called tendering of sulphur black.
Normally, dyers applys the urea, sodium acetates after dyeing as buffer to neutralize the formed acid, however, it only has a very limited effect and not last long.
Anti-tender SAT, a powerful anti-tendering agent for sulphur black, which is not a buffer system. It effectively reacted with the instable sulphide and polysulpide groups and forms a stable complex. So no acidic salt will be generated during the storage, even in a hot and humid condition.
AATCC 26 – Ageing Test (135Cx6 hours)
Tear strength ASTM 1424 – Elmendorf (Weft side :N)
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Ageing Test (135Cx6 hours)
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Before
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After
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Sulphur black dyed fabric
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7
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3.6(drop - 48.6%)
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Sulphur black dyed fabric with treaded + Antitender SAT
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7
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6.4(drop – 8.5%)
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* By padding:
8-10 g/l Antitender SAT
* By Exhaustion:
8-10 % Antitender SAT
20 minutes at 40ºC
Liquor ratio 10:1
