The line density of fiber refers to the thickness of the fiber. The length of the fiber refers to the length of the fiber.
Textile fibers must have a certain line density and length to make the fibers close to each other and spin the yarn depending on the friction between the fibers. Therefore, the textile fiber has a certain line density and length, which is one of the necessary conditions for textile processing and the use of the product.
The line density of textile fiber is closely related to the yarn and fabric made from textile processing. In general, the fiber line density is lower and the uniformity is better, which is beneficial to the textile processing and the quality of the products. In the influence of fiber linear density on the wearability of fabric, the fabric made of finer fiber is softer and glossy. The fabric made of finer fiber can produce lighter fabric and also can produce breathable and silk like fabric. But the fine fiber fabric made of easy fuzzing and pilling, crude fiber fabric can be used to manufacture is stiff, rough and thick fabric.
In the same way, the length of textile fiber is closely related to the quality of textile and product. Long fiber length, good length and short fiber content are good for textile processing and product quality. Under the same conditions, the fiber is longer, and the yarn strength is high, the evenness is uniform, and the surface of the yarn is smooth. The fabric is made of fabric with good fastness, bright appearance and no hair and pilling. In addition, on the premise of ensuring the quality of a certain yarn, the longer the fiber is, the finer the yarn can be spun, which can be used to make thinner fabrics. For the shorter length, the length is more important than the line density, for example, the length is the most important index in the grade and pricing of cotton.
In textile fibers, the linear density and length of natural fibers are not uniform. Sometimes the difference is bigger. It varies with fiber varieties and growth conditions. The chemical fiber is made artificially, and the line density and length of the fiber can be controlled and determined artificially in a certain range according to the requirements of fiber processing and use.