Why Need To Do Pretreatment Before Dyeing The Textile? - YULONG SAFETY

Why Need To Do Pretreatment Before Dyeing The Textile?

protective fabric from Yulong Textile

Without dyeing and finishing, fabric is called original piece or greige. There is only a little supply market for greige, while most of the greige will be processed into blanch cloth, color cloth or figured cloth for the use of the consumer. There are a considerable amount of impurities in the greige, including the cotton fiber concomitant with impurity, warp of sizing agent and chemical fiber of oiling agent in weaving and oil contamination cleaved in the processing of spinning, etc. If we do not clean up these impurities, not only will these impurities influence the color and feel but also influence the hygroscopic properties of fiber, so that the color will not be asymmetrical and bright. What is more, it will also influence color fastness.

Pretreatment aims to remove various impurities on the fabric under the condition of pimping damage and make the greige becoming dyeing semi-finished product which are pure white, soft and having good wetting property. Pretreatment is a preparatory process in dyeing process, and it is also called scouring and bleaching. There are some processes for cotton fabrics, such as preparation, singeing, desizing, scouring, bleaching, mercerizing and so on. As for different kinds of fabrics, there are different requirements for the pretreatment and different production conditions in different area factories, so in the pretreatment workshop, the producing process and technological conditions are all different.