| 配方类型： |
TEXTILES |
| 配方说明： |
Bleaching of Rayon |
| 配制方法： |
The bleaching of rayon is always a difficult and dangerous operation because the cellulose has already been substantially degraded by the solubilizing procedure. Thus rayon is much more susceptible to chemical action than is cotton. Minute traces of iron and other metals inn rayon cause catalytic decomposition of the peroxide and result in the decomposition of the rayon to such an extent that holes will occur wherever iron is present in any quantity, for example, at knots. The use of "Tetrine" (sodium ethylenediamine tetraacetate) in rayon bleaching baths is no guarantee that holes will not come in the goods at the knots because the quantity of "Tetrine" used is rather low in comparison with the amount of iron present in one specific knot. If the fabric is worked for sufficient length of time in a "Tetrinne" bath before bleaching, all of the iron can be eliminated. It is generally recognized that "Tetrine" is a necessary component of the bleaching bath and that it increases the depth of bleach, increases the |
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