Process of Pre Dyeing a Carpet

Pre-dyeing involves various dyeing processes where the yarn is dyed prior to tufting. The most common of these methods is referred to as solution dyeing. Included in this dyeing method are solution dyeing, space dyeing, stock dyeing, and skein dyeing. Solution dyeing is obtained by pre-heating to the polymer melt point, where it obtains a liquid state. At this point, dye pigments are dispersed into the polymer melt to obtain the desired color. This now colored polymer melt is extruded through a device known as a spinneret, which is similar to a showerhead. As the polymer melt is extruded, the fiber cross-section is determined by the shape of the holes in the spinneret and the extruded fiber is air-cooled and solidified. Because solution dyeing dyes the fiber throughout, rather than impregnating dye into the fiber, this method of dyeing produces the most effective stain cleanability of all fibers. Space dyeing, referred to also as yarn dyeing, is a process used primarily in various types of commercial carpet loop constructions made from or including the use of continuous filament nylon. In this process of dyeing, two or more different colors are essentially printed along the length of the fiber to create a multi-color affect in short lengths of the fiber that typically appear as horizontal or diagonal stripes. This is done by printing other colors on the base color by knitting the yarn into narrow tubes. The tubes are steamed and dried. The yarn is then de-knitted and wound onto cones for tufting or warping. Space dyed nylon is commonly used in carpet made primarily from solution dyed yarn to provide accent color. Skein dyeing also referred to as another form of yarn dyeing is similar to stock dyeing. Skein dyeing involves a process where yarn is wound into large skeins that are hung in dye vats and then dyed to produce smaller dye lots. After dyeing the yarn is then wound onto cones. Skein dyeing is often used to dye custom colors. Stock dyeing is considered to be the oldest method of dyeing carpet yarns. In this process, large quantities of staple yarns are placed in a large vat ("kettle"), and are dyed under pressure using non-water soluble disperse dyes. Once dyed, the kettle is drained and the yarns are then centrifuged to remove excess water. Stock dyed yarns must go through the spinning and heat-setting process. The vast majority of polyester fiber is dyed by this method. For more info of this topic, check the links below: carpet laying auckland