Yarn is a thin and long product made by twisting fibers or filaments once, with tensile strength and flexibility. The strand is a product made by combining two or more yarnsChina polyester FDY Yarns Suppliers and twisting for the second time. Its fineness, strength and uniformity are all higher than that of yarn. Strong is a product made of strands and all twisted for the third time. There are many varieties of yarn, and the methods of hair are different. This article divides them according to their structural characteristics.
(1) Spun yarn
The yarn composed of cotton, wool and other fibers by twisting and entanglement is called spun yarn. Its structure is complex and slightly different due to different spinning and twisting methods. Generally speaking, in the center of the yarn is a yarn core composed of dense fibers, and on the surface of the yarn there is a fluff area formed by the exposed fiber ends. The structure of an untwisted spun yarn shows that there are more and more complicated entanglements between the surface of the yarn core than the filament yarn. There are many fiber knots in low-quality spun yarn. Because the fibers are randomly arranged, coupled with changes in twist and fineness, resulting in coarse details in the yarn length direction. With the different adding methods, the quality and uniformity of spun yarns are still very different. The spun yarn has a bulky structure, a plump appearance, good thermal insulation and comfort; this is mainly due to the air contained in the voids in the yarn.

(2) Filament yarn
The silk or chemical fiber monofilament is combined with multiple roots, and a small amount of twisting is added to form a filament yarn. Smooth filament yarn (not deformed) is uniform, shiny and strong. Chemical fiber filament yarn is used as clothing material. Its characteristics are that the fabric is smooth, colored, easy to wash and dry; but it lacks the warmth and comfort of natural fiber fabrics. Monofilament yarns are often thicker and are used for fishing nets. Carry bags.
(3) Bulk yarn
Bulk yarn itself is spun yarn or filament yarn, but it has larger volume than the original yarn, bulky and soft. It includes the following three types;
1. Bulk yarn: Acrylic yarn fiber is thermoplastic. When it is heated, it will produce greater elongation, and then it will be cooled and fixed to form high shrinkage fiber. This kind of fiber is blended with ordinary fiber to make spun yarn. After steaming, the high shrinkage fiber produces longitudinal shrinkage and gathers in the core of the yarn. The ordinary fiber forms crimps or loops and bulges to make the yarn structure become Bulking, showing increased volume, this is the bulked yarn. Polyester filament

2. Textured yarn is the filament yarn that has been deformed. In the production process, some methods are used to make the silk fiber produce long-lasting crimps, loops and buckles, so the gap between the fibers increases and the yarn body is bulky. Therefore, the textured yarn has the important characteristics of spun yarn-it is warm and breathable.
3. Stretch yarn Stretch yarn has a high degree of elongation (3-5 times) and recovery ability. When it is fully stretched, it is like a normal filament yarn; when it is fully relaxed, it is like a bulked yarn. Most stretch yarns are made of thermoplastic filaments (nylon). The filaments are subjected to false twist and heat setting to produce long-lasting crimps, but there is no entanglement between the filaments. The knitted underwear made with it has a close feeling.
(4) Fancy yarn (thread)
Fancy yarn has a fancy appearance for decoration. There are many varieties and production methods. The structure of fancy yarn is composed of core yarn, decorative yarn and fixed yarn. The core yarn bears strong force and is the main yarn; the decorative yarn is wrapped around the core yarn with twist to form an effect; the fixed yarn is wrapped around the outer periphery of the decorative yarn with the opposite twist direction to fix the pattern, but there are cases where the fixed yarn is not used. The following introduces the names and characteristics of several common fancy yarns (threads);
1. Knotted yarn The decorative yarn is twisted and wound several times in the same place.
2. Spiral yarn is made by merging and twisting two yarns with different fineness, twist and type.
3. Thick knotted yarn The soft and thick fiber clumps are attached to the core yarn and wrapped with solid yarn.
4. Loop thread The decorative thread forms a closed loop shape and is wrapped with solid yarn.
5. Knotted thread The decorative yarn is wound on the core wire in a spiral manner, but the loop is thrown at intervals.
6. Chenille thread clamps horizontal decorative yarn in the core thread. The end of the decorative yarn is loose and plush.
7. Diamond-shaped metal wire Wrap another color around the outer circumference of the metal core wire (made of aluminum foil or sprayed metal material and covered with a transparent protective film). Thin decorative wires and fixed wires have a diamond pattern effect.
(5) Composite yarn (thread)
The composite yarn (thread) is uniform on the outside and consists of yarns of different components. There are two types:
1. Core-spun yarn Its center yarn is covered by fiber or another yarn. For example, the elastic thread has a rubber band in the center and yarn wrapped around the outer circumference. Another example is polyester-cotton yarn, which is wrapped with high-quality polyester filaments. The cotton shell makes the yarn sewable, and the polyester core makes the yarn strong.

2. Wrapping yarn Wrap filaments around the outer circumference of untwisted fiber bundles (short fibers or filaments).