Traditional bulk cotton fiber dyeing predominantly employs intermittent vat dyeing equipment. Independent processing in single vats is prone to issues such as color variations between batches and uneven dyeing, coupled with cumbersome procedures and substantial transfer workload, making it difficult to meet the demands of high-quality color spinning production. Bulk fiber continuous dyeing machines break through the limitations of intermittent dyeing, enabling continuous operation throughout the entire process of bulk fiber dipping, fixing, and washing, and are suitable for dyeing and processing various bulk fibers such as cotton and viscose.
The loosely packed fibers, after undergoing a bleaching pretreatment, are evenly spread out on a specialized mesh belt that allows water and air to permeate. As the mesh belt moves forward at a constant speed, the fibers maintain a loose and flat spreading state throughout the process. Initially, the fibers enter the padding and dyeing unit, where the dye solution evenly penetrates both the interior and exterior of the fibers, ensuring uniform coloration without local shading or color differences. After the padding and dyeing process, the fabric moves into the low-temperature steaming and fixing section. In this mild and stable temperature environment, the dye fully binds with the fibers, completing the fixing reaction and enhancing the stability of dye adhesion.
After fixing the color, the fibers enter multiple spray washing units to clean the surface floating color and residual auxiliaries layer by layer, avoiding the accumulation of floating color that affects the yarn color. The equipment can precisely adjust the thickness of the material, running speed, dye concentration, and steaming duration, adapting to the dyeing needs of different colors and materials of loose fibers. The continuous processing mode ensures uniform dyeing parameters for each batch of fibers, resulting in better color consistency, narrower color difference range, and the dyed fibers can be directly sent to the spinning process, forming an integrated production chain of bleaching, dyeing, and spinning.