The main intrinsic technical properties of cotton fiber are fiber length, fiber fineness, fiber strength and fiber maturity.
Fiber length is the distance between the two ends of a straightened fiber. There are different methods for measuring fiber length. The length that is measured by hand pulling ruler is called pulling staple length. The length measured by the carding method is called the carding length. The length measured by cotton fiber photoelectric length meter is called photoelectric length. The length measured by a high capacity fiber analyzer is called span length and the common used one is 2.5% span length. Generally, it is: carding length ＞ pulling staple length, photoelectric length ＞ 2.5% span length. Cotton fiber length of is closely related to the yarn strength. Spinning with longer fibers will increase the length of cohesive force between fibers. When the yarn is subjected to external force, the fiber is not easy to slip, and the yarn strength is higher.
Cotton fiber fineness refers to the degree of thickness of the fiber. That is the diameter of fibrocyte. Because it is difficult to determine the diameter of cotton fiber directly, and the main measure of cotton yarn thickness is the weight fineness, as the length per unit weight, so it is usually to use weight fineness to describe the fiber thickness. At present, air quantity flow meter is commonly used to measure the thickness of fiber. That is, using the principle of air flow to rapidly measure the specific surface area of the fiber and estimate the fineness of the fiber, which is indicated by Micronaire. Fiber fineness is closely related to yarn strength. Since the cotton yarn is made of multiple fibers, the yarn strength is not only determined by the strength of the fiber itself, but also related to the number of fiber roots per unit yarn fineness, the degree of relative slip between the fibers and the evenness of the strip. For spinning high-count yarns, it can only use raw cotton with longer fibers and better fineness.
Cotton fiber strength refers to the breaking strength. If other indexes are basically the same, the fiber strength is positively correlated with the quality of yarn and cloth. For the spinning speed of modern spinning equipment is higher, the fiber strength is high, which plays an important role in reducing the breakage rate and improving the production efficiency.
Fiber maturity is an important index to reflect the thickening degree of fiber cell wall. In the case of fibrocyte with similar diameters, the cell wall is thicker, the maturity is higher. The fineness, Micronaire, strength and dyeing characteristics of cotton fiber are closely related to the maturity.
High-quality raw cotton fiber requires that the main physical properties must be coordinated. Namely, the length, strength, fineness and uniformity of the fiber should match with each other reasonably. A single good indicator does not represent good quality of whole product.
Post time: Nov-09-2022