Setting of Dyebath(s)
For dissolving the dyes, de-ionised water should be used whenever possible, if not available drinking water of as low as possible hardness can be used. Hard water causes a reduction of the adsorption power.
Poor water quality leads to heavier bleeding during sealing process and may cause precipitation and or bath turbidity. Water containing softening agents is unsuitable and care should be taken to ensure the water is largely free from chlorides, phosphates, silicates and iron. Water sterilised by chlorination is suitable.
When setting up a dyebath, care must be taken that the dyestuff is well dissolved. It is preferable to dissolve the dyestuff with hot water (60-80 ⁰C) in a separate container (using about 5-parts of water for every 1-part Dyestuff).
If pH buffer is used, it should be added before the dyebath is topped up to the final bath volume. Finally, the pH is checked and if necessary corrected, then the bath is brought to the dyeing temperature.
Some dyestuff eg Anodye Blue 2LW and Blue G are not fully soluble in the amounts of water recommended for stock solutions. These dyes are suggested to be added to the water bath as they are and the suspension if first brought into an even state distribution before heating to dissolve.
Experience has shown that a freshly set bath does not develop its definitive dyeing properties until a certain time has elapsed. We suggest to prepare the bath a few hours before the commencement of dyeing. This is strongly recommended in the case of the Anodye Deep Black MLW. The waiting time can be shortened by heating up the bath to temperatures of ~80 ⁰C