The Cuticle of Wool

Friction between wool fibres is smaller than friction between other fibres. This is explained by a thin fibre coating, the epicuticle, which was discovered by means of the electron microscope. The epicuticle is resistant to chlorine, acids, and enzymes. Alkaline treatment perforates it. The cuticle below the epiouticle consists of an intermediate layer, the exocuticle, and the scale substance proper, the endocuticle. The epicuticle prevents diffusion of large molecules, e. g. –those of dyes. The Allwörden reaction and staining tests for damage are explained by the existence of the epicuticle. It is easily damaged by mechanical treatments. Its removal gives an increase in fibre friction and thereby anti–felting properties. The importance of the frietional properties of fibres for spinning and wearing qualities is stressed.