Core-spun yarn is generally made of synthetic fiber filament with good strength and elasticity as the core filament, and is wrapped with cotton, wool, viscose fiber and other short fibers and twisted together. Made of yarn. Core-spun yarn combines the excellent properties of filament core yarn and outer short fiber. The more common core-spun yarn is polyester-cotton core-spun yarn, which uses polyester filament as the core yarn and is wrapped with cotton fiber. There is also spandex core-spun yarn, which is a yarn made of spandex filament as the core yarn and wrapped with other fibers. Knitted fabrics or jeans made from this kind of core-spun yarn can stretch freely and fit comfortably when worn.
The main purpose is to strengthen the cotton canvas and maintain the water repellency of the cotton fiber when it expands when exposed to water. It uses polyester to have tensile strength when it gets wet in the rain. Stretch, tear resistance and shrinkage resistance. At this stage, core-spun yarns have developed into many types, which can be summarized into three categories: short fiber and short fiber core-spun yarns, chemical fiber filament and short fiber core-spun yarns, and chemical fiber filament and chemical fiber filament core-spun yarns. At present, most of the core-spun yarns generally use chemical fiber filaments as the core yarn and are wrapped with various short fibers to form a unique structure of the core-spun yarn. Commonly used chemical fiber filaments for its core yarn include polyester filament, nylon filament, spandex filament, etc. Outsourcing short fibers include cotton, polyester-cotton, polyester, nylon, acrylic and wool fibers.
In addition to its special structure, core-spun yarn also has many advantages. It can make use of the excellent chemical fiber filaments of the core yarn. The physical properties and the performance and surface characteristics of the outer short fiber can give full play to the strengths of the two fibers and make up for their shortcomings. For example, polyester-cotton core-spun yarn can give full play to the advantages of polyester filaments that are crisp, crepe-resistant, easy to wash and quick-drying, and at the same time, it can also take advantage of the outer cotton fiber’s good moisture absorption, low static electricity, and resistance to pilling. The woven fabric is easy to dye and finish, comfortable to wear, easy to wash, bright in color and beautiful. Core-spun yarn can also reduce the weight of the fabric while maintaining and improving the properties of the fabric. It can also make use of the different chemical properties of the chemical fiber filament and the outer fiber. During the fabric dyeing and finishing process, chemicals are used to rot away part of the outer fiber to make Burnt-out fabrics with three-dimensional pattern effects, etc. The use of core-spun yarns. Currently, core-spun yarns with cotton as the sheath and polyester as the core are the most widely used. They can be used to produce student uniforms, work clothes, shirts, bathrobe fabrics, skirt fabrics, sheets and decorative fabrics, etc. An important development in core-spun yarns in recent years is the use of core-spun yarns with polyester cores covered with viscose, viscose and linen, or cotton and viscose blends, as well as cotton and silk or cotton and wool in women’s clothing fabrics. Blended with covered core yarn, these products are very popular among people.
According to different uses of core-spun yarns, the current varieties of core-spun yarns mainly include: core-spun yarns for clothing fabrics, core-spun yarns for elastic fabrics, and decorative yarns. Core-spun yarn for fabrics, core-spun yarn for sewing thread, etc. There are also many spinning methods for core-spun yarn: ring spinning, electrostatic spinning, vortex spinning, self-twisting spinning, etc. At present, my country’s cotton spinning industry mostly uses cotton ring spinning to spin core-spun yarn.
Spinning process~
The current spinning process There are two technological processes for core yarn, taking the processing of polyester-cotton core yarn as an example.
Carding system:
Cotton: Carding one end of cotton and roving- Spun yarn (core-spun).
Combing system:
Cotton: one carding and one roll of cotton are rolled together One is combed, one is combined, one is combined, two is combined, three is roving and one is fine yarn (core-spun).
In the actual processing process, the choice of core-spun yarn process depends on the yarn requirements and the yarn count to be spun. The general principle is, If you can use rough combing, you don’t need combing. If you want to use a combing system, the process can be shortened as much as possible to reduce production costs. For example, some manufacturers’ combed cotton slivers have good unevenness, fiber straightness and parallelism, and can meet the coating requirements after passing through one pass and drawing. Then, the process can be adopted:
Cotton: One roll of cotton, one combed one, one roving one and one fine yarn (core-spun) ).
Raw material selection:
Selection of core wire:
The fineness of the core filament and the number of single filaments in it should be selected according to the fabric use and spinning count. For core filaments of the same fineness, the thinner the single filament, the more the number of core filaments, and the softer and smoother the fabric. On the contrary, the fewer the number of core filaments, the better the stiffness and crispness of the fabric. For coated products, there is no need to consider the gloss of the core filament, and glossy core filaments can be used to reduce production costs; if exposed products are produced, the gloss of the core filament should be considered, and glossy filaments should be used as little as possible, which will cause the product to cause aurora and affect Effect.
For example, 11.8tex (50s) polyester-cotton core-spun yarn can be used to make skirt materials and=”text-align: left;”>Jointing length – use both hands: That is, one hand is used to join and the other hand is used to cut the filament core with scissors. This is the main feature of the core-spun yarn joining operation. According to the test, when the length of the core-spun yarn joint is about 40-50mm, it can ensure that the strength of the joint yarn section is close to that of the normal yarn section. In addition to emphasizing the “simultaneous” use of both hands, the elastic core yarn joint also pays attention to strengthening daily mechanical maintenance work to achieve The suction flute tube has the same height, and the front and middle top rollers are the same to ensure the standard joint length.
Bare core tail – before using both hands to join the joint, the filament core should be pre-cut once so that the filament loses suction instantly. The elastic force retracts to the center of the outer fiber bundle. If you make full use of the sharp rebound of the filament and master the filament reset opportunity joint, you can eliminate or significantly reduce the “bare core tail” caused by the joint.
Joint hollow core – after repeated practice, the method of untwisting and then twisting can eliminate the “hollow core” of the joint . Untwist 20mm of the broken yarn end wound on the bobbin, let the spandex yarn retract freely, and pull out the outer fiber of the spandex yarn, then twist the untwisted yarn end appropriately by hand, and then join , so that the joint quality is good.
Purpose~
Core-spun yarn At present, the core-spun yarn with cotton as the skin and polyester as the core is the most widely used and can be used to produce student uniforms, work clothes, shirts, bathrobe fabrics, skirt fabrics, sheets and decorative fabrics, etc.
An important development of core-spun yarn in recent years is the use of viscose fiber, viscose fiber and linen or cotton and viscose fiber blended yarn in women’s clothing fabrics. Core-spun yarns covered with polyester cores, and core-spun yarns covered with cotton and silk or cotton and wool blends are very popular.
According to different uses of core-spun yarns, the current varieties of core-spun yarns mainly include: core-spun yarns for clothing fabrics, core-spun yarns for elastic fabrics, and decorative yarns. Core-spun yarn for fabrics, core-spun yarn for sewing thread, etc.
There are many methods of spinning core-spun yarn: ring spinning, electrostatic spinning, vortex spinning, self-twisting spinning, etc. At present, my country’s cotton spinning industry mostly uses cotton ring spinning to spin core-spun yarn.
