Common yarn dyeing methods
(1) Out-of-skein dyeing
Skein dyeing is a dyeing method that converts staple yarn or filament yarn into a series of skeins on a reel and then dyes them in various dyeing machines.
(2) Package dyeing
Skein dyeing is a dyeing method that winds staple yarn or filament yarn on a bobbin full of holes (the winding density should be appropriate and uniform, generally called "loose cone"), and then puts it on the dyeing column (also called bamboo spindle rod, plug rod, etc.) of the yarn carrier (also called flat plate, hanging plate, yarn rack, etc.) of the dyeing machine, and puts it into the package dyeing machine. With the help of the main pump, the dye liquid penetrates and circulates between the yarns or fibers on the package, and the dyeing method is package dyeing.
(3) Warp beam dyeing
According to the requirements of the color and quantity of the warp yarn of the colored fabric, the original yarn is wound on a perforated coil on a loose warping machine to form a loose warp beam (which can be regarded as a large bobbin), which is then installed on the yarn carrier of the dyeing machine and placed in the warp beam dyeing machine. With the help of the main pump, the dye liquid penetrates and circulates between the warp yarns or fibers to achieve immersion dyeing. The method of obtaining a warp yarn with uniform color is called warp beam dyeing.
(4) Warp beam pad dyeing
Warp beam pad dyeing is mainly used in the production and processing of denim with colored warp and white weft. It introduces a certain number of thin beams into each dyeing tank, and after repeated immersion, multi-rolling, and multiple ventilation oxidation, it realizes the dyeing of blue (or sulfur, reduction, direct, coating) dyes. After pre-drying and then sizing, a warp beam yarn with uniform color can be obtained, which can be directly used for weaving. The dyeing tanks during warp roller dyeing can be multiple (sheet machine) or one (ring machine). This equipment used in conjunction with sizing is called a sheet dyeing and sizing combined machine.
(5) Yarn bundle dyeing
This is also a special dyeing method for denim warp yarn. The dyeing process is to first bundle 400~500 raw yarns into a ball shape, and then repeatedly immerse, roll and oxidize several bundles (such as 12 bundles, 18 bundles, 24 bundles, 36 bundles) of yarn in multiple dyeing tanks. After the indigo dyeing is achieved, the warp and sizing of acrylic yarn bundles can also be rolled.
(6) Bread yarn dyeing
Similar to the dyeing of loose fiber and cheese yarn
Special dyeing method for yarn
Like fabrics, yarns also have local dyeing, such as printed knots, segment dyeing, tie-dyeing, printing, discharge dyeing, gradient, etc.
1. Printed knots
According to the design requirements, a small section (such as 0.5~1CM) of color is printed at a set distance on the spread skein. It can be the same color, but most of them are colorful. It must be noted that the spacing must be irregular and unequal, otherwise "turtle back" or "landscape" will appear on the cloth
2. Segment dyeing
Several dyes are dripped on different parts of the spread skein at the same time, and after vacuum absorption or squeezing, the color is fixed and washed. Compared with printed knots, the color segments are longer, the spacing between white yarns is smaller, and even two adjacent colors will appear "matched colors" on the yarn. Segment dyed yarn is more used in knitted fabrics
3. Tie-dyeing
Tie the part of the skein tightly with rope (or wrap it with plastic film), and then dye it. As a result, the tied part is left blank, the tied part has some color from dark to light, and the untied part is evenly colored, and the product has a unique charm.
4. Printing
(Printing warp) This method is generally used to produce printed warp machine fabrics. Print patterns on the warp (not on the weft), and the product style is hazy, like flowers but not flowers. When printing warp, you can first fake weave (knitting method is to print first and then warp, and weaving method is warp-fake weaving-printing), or you can directly on the warp.
4. Gradient dyeing (seven-color silk)
Dye different parts of the skein (silk) in the dye solution for different times, so that each frame of yarn presents a gradient color from light to dark without obvious boundaries, such as the seven-color silk thread of traditional Chinese embroidery.
