Cotton cone yarn dyeing,  process mainly consists of the following five steps:

PRETREATMENT

This step primarily removes natural impurities (cottonseed hulls, waxy substances, etc.) and pigmentum from the yarn, enhancing its whiteness and capillary effect to create conditions for dyeing processing.

DYEING

Each type of fiber has its unique dyeing characteristics, and yarn dyeing process is formulated based on  properties of cotton fibers (cellulose fibers) and reactive dyes. The process of package yarn dyeing involves applying pressure to dye solution in cone yarn dyeing machine using a pump, allowing the dye solution to penetrate from inner layer to outer layer of package yarn, thereby achieving uniform dyeing.

SOAPING

After dyeing, a large amount of hydrolyzed and unreacted dye remains on the surface of the yarn, which must be removed by adding soaping agent and washing under high temperature conditions (known as soaping). The role of soaping is to remove the floating dye on the yarn, improve the color brightness, and meet the fastness requirements of customers.

COLOR FIXATION

After soaping, for dark and medium color, fixing agent is added to achieve the processing requirements of subsequent finishing. The function of fixing agent is to form a protective film on the surface of the yarn to prevent dye from falling off during subsequent finishing processes.

SOFTENING

During the dyeing process, natural waxy substances on the yarn surface are destroyed, making the yarn feel harder. Therefore, after dyeing, a certain compound is added to the yarn to reduce friction between yarns, facilitating winding and subsequent weaving processes.