Surface Quality
Optical measurement of the cumulative length of protruding fibers provides a precise value for the surface smoothness of a yarn. The uster s3 hairiness index specifically counts the number of fibers that extend 3 millimeters or more from the main yarn body. This value is a primary measure of how the finished linen fabric will feel and how it will perform during weaving.
Measurement Technology
Laser sensors track the shadow of the yarn as it moves at high speeds through a testing head to detect every fiber that breaks the surface plane. Because flax is a relatively long and stiff fiber, it tends to create more hairiness than cotton if the spinning rings or travelers are worn. High values in this index suggest that the fibers are not being properly bound into the yarn core during the twisting process.
Fuzz increases. Maintaining low hairiness is essential for preventing the yarn from sticking to adjacent strands in the loom.
Process Control
Excessive hairiness leads to a fuzzy appearance in the fabric and increases the risk of pilling. Appearance degrades. Controlling this index during the spinning stage ensures that the resulting cloth meets international standards for premium linen.
