Much of merinos comfort advantage is due to the fact that it is a hygroscopic fibre capable of absorbing and desorbing moisture vapour from the external environment or body microclimate (between the body and the garment layers). Synthetic fibres are not hygroscopic, a fact illustrated in this graph, in which the standard regain of various fibres is charted (this is the amount of water in the fibre expressed as a percentage of its dry weight in standard conditions – 20°C, 65% relative humidity). 18 16
Standard R egain (%)
14 12 10 8 6 4 2 0