Bleach Washing Problem
Bleach can be used to decolorize indigo from garments. In this process a strong oxidative bleaching agent such as sodium hypochlorite or KMnO4 is added during the washing. De-colorization process is usually more apparent depending on strength of the bleach liquor quantity, temperature and treatment time.
It is preferable to have strong bleach with short treatment time. After bleach washing, there should be neutralization to minimize yellowing.
Limitations of bleach washed in the below:
Difficult to control in bleach processing time
Bleach is harness chemicals so it may cause damage to cellulose resulting in severe strength losses or breaks or pinholes at the seam, pocket, etc.
Harmful to human health and causes corrosion to stainless steel.
Required neutralization treatment.
Residual chlorine in garments may occur Yellowish.
Pass into the effluent where they cause severe environmental pollution
To avoid bleaching problem of a garment, the below techniques using
If the strength of garments is losses then should be used Bleach Activator to reduce bleach dosages and processing time also
To remove Yellowish after bleach, should be neutralization with Hydrogen per oxide or Meta.
Control pH 10.5-11 before bleach pour into the machines
There are another Option of Bleach like bleaching with Laccase, Bleaching with Hydrogen per oxide, Eco Bleaching. It helps to reduce bleach washing problem.