ISO 21046:2018 PDF

Overview

ISO 21046:2018 specifies a standardized test method for determining the size (linear density) of silk yarns in all package forms (skeins, cones, bobbins). Applicable to raw silk, tussah, dupion, thrown silk and similar natural-silk yarns, the standard is not applicable to spun silk yarns. It defines sampling, conditioning, apparatus, weighing, drying and calculation procedures so that results (expressed in dtex or denier) are comparable across laboratories and commercial transactions.

Key topics and technical requirements

• Definition of size: linear density (mass per unit length), expressed in dtex (or denier; 1 den = 0.9 dtex per ISO 1144).
• Sampling & sample length: sizing skein length is 112.5 m (e.g., 100 revolutions on a 1 125 mm wrap reel or 112.5 revolutions on a 1 000 mm reel).
• Sample quantity: a multiple of 50 skeins; default test amounts are 100 skeins for nominal size ≥78 dtex and 200 skeins for