Knit dyeing:
Knit dyeing is a technique of dyeing knitted fabrics. The dyeing of knitted fabrics occurs in the exhaust method or in batch-wise process. The Knit dyeing process is near similar to the yarn dyeing process but there is some difference in quality measurement. Generally, all types of single jersey, double jersey, and their derivatives are dyed in a different way. Flow chart of knit dyeing describes shortly.
Process Flow Chart of Knit Dyeing
Grey fabric inspection
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Batching
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Fabric turning
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Loading to the m/c
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Pre-treatment (Scouring & Bleaching)
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Dyeing
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Dewatering
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Drying
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Compacting & Calendaring
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Final inspection & packing
Knitted fabrics undergo a series of different chemical processing treatments. Such as scouring, bleaching, dyeing, hydro extractor or dewatering, stitching, stentering, compacting, softener padding, relax drying, final inspection. These processes are carried out to impart a particular property related to that process like scouring for absorbency, bleaching for whiteness, dyeing to impart color to the fabric. And finishing for improving the softness and handle of the fabric. The properties of the knitted fabrics are influenced by various parameters. Like raw material, yarn structure, fabric structure, processing stages, and finishing. The process adopted affects the fabric properties and its overall performance.
During the finishing process, internal stresses stored during spinning, knitting is removed. The fabrics attain an almost fully relaxed state. By adopting different processes and finishing methods, different kinds of knitted fabric in a sense of aesthetic and utility properties can be produced from the same unfinished fabrics. The knits goods, in contrast to the woven cotton fabrics, are easily starched and their loops would get distorted under the stretching tension of the dyeing cylinders. Special drying machines have, therefore, been developed to dry knitwear with the minimum of tension.
Author of this Article: Rana Sohel Executive Engineer Sunman Textile Mills Ltd. Chittagong Cell: +8801912-420118 Email: rsohel07tex@gmail.com