Water Marks found in 100% Cotton:

 

Question:
Suggestion for removing the water mark before processing:

Answer:
Suggestion for removing the water mark before processing:
In grey unprocessed stage if cotton fabric is exposed to water spotting when it is in pile form and if it is not noticed before taking for processing, a big head ache will land up with the processing people. Fabric taken for desize, mercerise, bleach and dye would show irregular shaped patches in the processed fabric.

This is may be due to either fungus formation on the wet areas or partial removal of size due to bacterial action under moist conditions. Whatever it may be, these patches would appear prominent only after dyeing or bleaching (OBA treated).

Mostly these patches your would come across during rainy season or while processing a fabric that was stored for very long time. If you are lucky enough to take processing in batch mode, you can very well eliminate the patches fro the next batch on wards.

Instead of going for peroxide bleach or mercerisation after desizing, you take the fabric directly for hypo bleaching. No extra alkali should be present during this process, except a wetting agent and sodium hypochlorite. After this process, you can take any route according to your necessity. Now you would not find any water mark in the processed fabric.

Always prevention is better than cure. So when storing the fabric is a ware house, always keep it closed with a polythene sheet to avoid these type of mystic problems, that you can notice only after damaging sufficient quantity of fabric.

Suggestion for removing the water mark before processing:
(1) If the fabric is in mercerised stage, try a hypo bleach, followed by peroxide bleaching.
(2) If the fabric is in dyed stage, you have to convert the dyed shade either in to a jet black (sulphur black) or some very dark shade and go for fresh lot.