Line density and length of fibers and yarns

Linear density and length of fibers The linear density of fibers refers to the thickness of the fibers. The length of the fiber refers to the length of the fiber.

Textile fibers must have a certain linear density and length in order for the fibers to entangle each other and to be spun into yarns depending on the friction between the fibers. Therefore, textile fibers have a certain linear density and length, which is one of the necessary conditions for textile processing and the use value of the products.

The linear density of textile fibers is closely related to the processing of the textile and the properties of the finished yarn and fabric. Under normal circumstances, the fiber density is low and the uniformity is good, which is beneficial to textile processing and product quality. In the influence of the fiber density on the wearing performance of the fabric, the fabric made of the finer fiber is softer and the gloss is softer, and the thinner fabric can be used to make the fabric which is lighter and thinner, and the air permeability and the silk-like effect can also be produced. Good clothing fabric. However, fabrics made of fine fibers are prone to pilling and pilling, while coarse fabrics can be used to make fabrics that are stiff, rough and thick.

Similarly, the length of textile fibers is also closely related to the quality of textiles and products. Longer fiber lengths, good length uniformity, and low staple fiber content are beneficial to textile processing and product quality. Under the same conditions, the fiber is long, the yarn strength is high, the strip is even, and the surface of the yarn is smooth. The fabric has good fastness, smooth appearance, and is not easy to fluff and pilling. In addition, under the premise of ensuring a certain yarn quality, the longer the fiber, the finer the spun yarn can be used to make a relatively thin fabric. For shorter lengths, length is more important than linear density. For example, in cotton grade and pricing, length is the most important indicator.

In textile fibers, the linear density and length of natural fibers are not uniform, and sometimes the difference is large. It varies with fiber type and growth conditions. While chemical fibers are manufactured by hand, the linear density and length of the fibers can be artificially controlled and determined within a certain range according to the requirements of fiber processing and use.

The bulked yarn is firstly blended into two yarns of different shrinkage ratios, and then the yarn is placed in steam or hot air or boiling water. At this time, the fiber with high shrinkage produces a large shrinkage. The center of the yarn, and the low-shrinkage fibers mixed together, are squeezed on the surface of the yarn to form a loop shape due to the small shrinkage, thereby obtaining a bulky, full-bodied, elasticized bulky yarn.

Core-spun yarns Core-spun yarns are generally made of synthetic fiber filaments with good strength and elasticity as core yarns, and yarns spun by short fibers such as cotton, wool and viscose. The core spun yarn combines the excellent properties of a filament yarn and an outer staple fiber. The more common core-spun yarns are polyester-cotton core-spun yarns, which are made of polyester filament yarn and are wrapped with cotton fibers. There is also a spandex core-spun yarn, which is a yarn made of spandex filaments and is made of other fibers. The knitted fabric or the jeans material made of such a core-spun yarn is stretchable and comfortable when worn, and fits comfortably.

Linear density of fibers and yarns

Linear density is one of the most important physical and geometric characteristics of fibers. It not only affects textile processing and product quality, but is also closely related to the performance of the fabric. Similarly, linear density is also the most important indicator of yarn. The linear density of the yarn affects the physical and mechanical properties, feel, style, etc. of the textile, and it is also an important basis for fabric design.

The linear density of fibers and yarns can be expressed in a variety of forms and is generally expressed as an indirect indicator proportional to the cross-sectional area of the yarn. Commonly used indicators are Tex (number), metric count, inch count, and denier. In general, the linear density of fibers and yarns are mainly divided into two types: long and fixed.

The fixed length system refers to the weight of a certain length of fiber or yarn. The larger the value, the thicker the fiber or yarn. Currently commonly used are tex, dtex, mtex, denier, and the like. The legal unit of measurement in China is a special system.

Turks is referred to as "special" and refers to the weight in grams of a 1000-meter-long fiber or yarn at a given moisture regain. Turks is commonly known as a number for cotton yarns.

In addition, the diameter of the yarn can also be expressed by the diameter. The diameter of the yarn is an important basis for fabric design and manufacturing process parameters. It can be measured under a microscope, but in actual production, the diameter of the yarn is converted by the number or count of the yarn and the density of the yarn. And got it.

In the linear density representation of the strand, the special number is expressed by multiplying the number of single yarns constituting the strand by the number of joints, such as 14 x 2. When the characteristics of the single yarns in the strands are different, they are represented by the sum of the single yarns, such as 16+18. The count system is expressed by dividing the number of single yarns that make up the strand by the number of strands, such as 50/2. If the number of single yarns constituting the strand is different, the count of the single yarn should be juxtaposed and cut with a diagonal line, such as 24/48.

The multifilament linear density of the chemical fiber is expressed by the number of filaments constituting the multifilament and the total number of texels. For example, 16.5 tex/30 f, indicating that the multifilament bus density is 16.5 tex, and the number of filaments is 30. The multifilament linear density of the chemical fiber or silk is the sum of the linear density of the monofilaments constituting the multifilament.