Optical Foreign Matter Detection Limits in Raw Cotton Blowroom Cleaners
Optical sorter limits depend on tuft opening, duct air velocity, and spectral contrast between white polypropylene and raw cotton fibers.
Seed Coat Fragment
Biological Contaminant
Biological debris left after the ginning process comprises small portions of the cotton hull that remain attached to the lint. A seed coat fragment is often more difficult to remove than pure leaf trash because of its strong mechanical attachment to the fiber. These particles are a primary source of small dark specks in the final fabric.
Ginning Impact
Modern high speed ginning can break the seeds. This increases the count of these fragments in the raw cotton.
Dyeing Quality
During the finishing process, the presence of a seed coat fragment creates visible flaws because the woody material does not absorb dye in the same way as the cellulose fiber. These fragments often appear as light or dark spots depending on the dye type and the maturity of the cotton. Inspecting the greige cloth before dyeing allows the mill to identify batches with high contamination levels.
Cleaning Efficiency
Carding and combing stages are designed to extract these impurities before the spinning process. If the seed coat fragment is not removed, it can be ground into smaller pieces that are almost impossible to extract later. Improving the settings of the openers and cleaners helps in maintaining the quality required for high grade yarn.