1.1 Fixed-length titer unit
Denier (D): Refers to the weight in grams of a 9000-meter-long fiber or yarn at a given moisture regain. For example: 1500D polyester raw silk means that the raw silk is measured 9000 meters, and its weight is 1500 grams. Others follow and so on.
Special number (tex): also called number, refers to the weight in grams of a 1000-meter-long fiber or yarn under a certain moisture regain. For example: 167tex polyester raw silk means that the raw silk is measured 1000 meters, and its weight is 167 grams. Others follow and so on. In the domestic industrial yarn and downstream products rubber canvas industry, people are more accustomed to using dtex instead of tex.
Decitex (dtex): refers to the weight in grams of a 10,000-meter-long fiber or yarn under a given moisture regain. For example: 1870tex nylon raw silk means that this raw silk is measured 10,000 meters, and its weight is 1870 grams. Others follow and so on.
1.2 Custom-made titer unit
Public count (Nm): refers to the length in meters of a 1-gram fiber or yarn under a certain moisture regain. For example: 20 public cotton yarn refers to the corresponding length of 1 gram of this cotton yarn is 20 meters. Others follow and so on.
British count (Ne): Refers to the multiples of 840 yards (0.914 meters) that a 1-pound fiber or yarn length has at a given moisture regain. For example: 20 inch cotton yarn refers to 1 pound (453.6 grams) of this cotton yarn and its corresponding length is 20 840 yards (ie 840x0.914x20 meters). Others follow and so on.
1.3 Application of fixed-length titer units and fixed-weight titer units
1) Standard logo
In terms of standard identification: for example, the specifications of industrial yarn are 1100dtex, 167tex, 2000D, etc.; the identification of cotton yarn is 10Ne, etc.; the identification of cord fabric is 1100 dtex/2, etc. The warp structure of EP-300 is identified as 1100 dtex/4 etc. Therefore, the titer unit has a wide range of applications in standard identification.
2) Visually judge and compare the thickness of fibers from the fineness value
Both kinds of titers are measurement units that represent the titer of fibers or yarns, but: in the custom-made titer unit, the larger the value, the thicker the fiber, and vice versa; the larger the value in the custom-made titer unit , representing the finer the fiber, and vice versa. The titer value and the thickness in the two measurement units are in the opposite direction.
2.1 Moisture regain rate
Moisture regain refers to the percentage of the moisture content in the textile material to the dry weight of the textile material, and the moisture regain is an index indicating how much moisture the textile material absorbs.
2.2 Actual moisture regain
The moisture regain measured under actual atmospheric conditions.
2.3 Standard moisture regain
Moisture regain measured under standard atmospheric conditions (temperature 20+/-2°C, relative humidity 65+/-3%).
2.4 Conventional moisture regain
In trade and cost accounting, in order to record the weight and check the price, the state makes uniform regulations on the moisture regain of various textile materials, which is called the public moisture regain.
3.1 Moisture content
The percentage of moisture contained in a textile material by weight relative to the moisture content of a textile material.
4.1 The role of twisting
The two sections of the sliver are rotated relative to each other, and the fibers in the sliver that were originally parallel to the yarn axis are inclined into a spiral. When the sliver is stretched by an external force, the inclined fibers will produce centripetal pressure on the yarn axis, so that there is a certain friction force between the fibers, which is not easy to slip off, and the sliver has a certain strength. For short fibers, twisting is a necessary means of yarn formation. For filament yarns and strands, the twist is to create a tight action that is not easily destroyed by lateral forces. The amount of twist and the combination of twist direction and twist in the yarn and fabric are closely related to the performance of the finished product and many physical properties.
When the yarn is twisted, the relative number of turns of the two sections is called the twist number. The number of twists per unit length of yarn is called twist. The length unit of special number system twist is 10cm or 1m.
Fabric density refers to the number of yarns per unit length in the weft and warp directions of the fabric, and is divided into warp density and weft density. Warp density, also known as warp density, is the number of warp threads per unit length of the fabric along the weft direction. The weft density, also known as the weft density, is the number of weft threads per unit length of the fabric along the warp direction. Warp density and weft density are expressed in root/10cm.
6.1 Creep phenomenon of fibers
Under the condition of constant tensile external force, the process in which the deformation of the fiber increases gradually with the continuation of the force time is called creep. Due to the existence of creep phenomenon, after a textile material is subjected to a load less than the breaking strength for a long time, the elongation at break will be reached due to the continuous increase of elongation, so that the textile material will break.
7.1 Fatigue properties of fibers
Fatigue is divided into static fatigue and multiple stretching fatigue.
Rest fatigue is the phenomenon of fracture under prolonged action of a constant tensile load less than the breaking strength.
Multiple tensile fatigue is a phenomenon in which the fiber or yarn is subjected to repeated cycles of loading and unloading for multiple times. Because of the gradual accumulation of plastic deformation, the fiber is partially damaged, forming cracks, and finally being destroyed.
8.1 Initial modulus
Fiber load elongation - the stress-strain ratio of the initial straight line part of the curve, when the straight line part is not obvious, the ratio of load to elongation and linear density (tex) at 1% elongation can be taken, in N/ tex. The size of the initial modulus indicates how easily the fiber deforms under a small load, which reflects the stiffness of the fiber. If the initial modulus is large, it means that the fiber is not easily deformed under a small load, the rigidity is good, and the product is relatively stiff; on the contrary, the initial modulus is small, the fiber is easily deformed under a small load, the rigidity is poor, and the product is relatively soft. The initial modulus of polyester is high, and the polyester fabric is stiff; the initial modulus of nylon is low, and the nylon fabric is soft and has no body bones.