Refined Material
Chemical cleaning is the process of removing natural waxes and oils from raw plant fibers. Scoured cotton is the result of a hot alkaline bath that dissolves non-cellulosic impurities to prepare the fiber for dyeing. Without this step, the material would be water repellent and would not absorb pigments evenly.
Wettability Change
Natural fibers are covered in a protective layer that resists moisture. Once a batch becomes scoured cotton, its ability to take up liquids increases dramatically. This transformation is measured by a drop test where a technician records how many seconds it takes for a water droplet to vanish into the surface.
Commercial Cleanliness
Buyers specify exactly how much oil and wax can remain on the fibers after processing. If scoured cotton still contains high levels of pectin, the fabric will feel stiff and may show patches of uneven color. Effective rinsing ensures all dissolved debris is washed away before the next stage.
Production Check
Samples are tested in the mill lab using ether extraction to check the efficiency of the wash. A high quality scoured cotton shows very low extractable matter and a bright white appearance. Meeting these specs is a requirement for all medical grade cotton products.
