4. Properties

4.1 Physical and mechanical properties

• Diameter: for monofilaments, it is customary to characterize its size by its diameter expressed in hundredths of a millimeter or in micrometers. In the case of yarns and fibers, size is characterized by the yarn's linear density.

• Linear mass or titre: tex is the unit of measurement for the linear mass of textile fibers and yarns; 1 tex represents the mass, expressed in grams, of 1,000 m of yarn.

Other units are also used:

• 1 dtex: mass expressed in grams of 10,000 m of yarn;

• 1 denier: mass expressed in grams of 9,000 m of yarn. This is an old unit that...