Uster Grades Offer Greater Clarity
Uster unveils Hairiness Grades for improved yarn hairiness.
TW Special Report
U ster Technologies AG, Switzerland, regularly publishes application papers and documents such as USTER® Yarn Grades and Uster Statistics, to help the textile industry worldwide compare and optimize yarn quality. Uster Yarn Grades help relate yarn defects as classified by measuring systems to process faults, and through appropriate settings help the spinner decide if the defects need to be eliminated or accepted. Uster Yarn Grades also help yarn buyers specify with even greater clarity the required quality level to the spinner.
Uster Statistics, last published in 2001, already included benchmarks for the hairiness index H for knitted and woven fabric.
Yarn hairiness as seen by the USTER® Tester 4 and Uster Quantum 2 clearer
Uster's Hairiness Grades help to visualize various levels of the hairiness index H for combed cotton yarns, such as Ne 60, shown here.
It is now well accepted that differences in yarn hairiness influence fabric hand. The hairiness index H and variation sh have been the most reliable measurement of hairiness variations in yarns for close to two decades. First introduced with the Uster Tester 3 in 1987, the hairiness measurement was implemented in on-line systems in 2002 on the Uster Quantum clearer. The hairiness measurement principal used on the on-line system is the same as that used on the Uster Tester 4. In order to fulfill a long-awaited request by spinners, Uster has made available its new Hairiness Grades. Spinners often have stated that they need to compare and understand hairiness levels for yarns in a simple form. The new hairiness grades help to visualize various levels of the hairiness index H for Ne 20 to Ne 60 combed cotton yarns. Further releases are planned for carded and compact yarns.
In conventional yarns, a relative hairiness increase of about H = 1 can be detected in the
fabric by the human eye. For compact yarns, hairiness variations are more critical due to the
improved evenness and must be detected immediately in the compact-spinning process. The Uster
Quantum clearer has the capability to detect and remove hairiness exceptions, based on programmable
limits for the entire production.The new Uster Hairiness Grades will help spinners better
understand and control hairiness variations. Hairiness grades may be obtained in printed form from
local Uster representatives or may be downloaded free of charge from Uster's website,