Resolving Microscopic Scale Loss in Mechanically Recycled Animal Hair and Wool Blends
Resolving microscopic scale loss in recycled animal hair requires high-tenacity carrier wool additions and proteomic mass spectrometry verification.
Cuticular Scale Height
Fibre Morphology
Microscopic relief on the surface of animal fibres determines the tactile and mechanical properties of raw wool. The cuticular scale height of wool fibres influences how easily they slide against one another during yarn spinning and fabric milling. This physical parameter is measured in micrometres from the fibre axis to the outer edge of each overlapping cuticle.
Surface Friction
High protrusion of scales increases the resistance to movement when fibres slide in the direction opposite to their growth. This directional resistance, known as the differential friction effect, arises directly from a higher cuticular scale height. The resulting interlocking of fibres under heat and moisture is the primary mechanism of wool felting.
Lab Measurement
Scanning electron microscopy and atomic force microscopy are the primary tools used to determine the surface geometry of keratin fibres. Examiners scan multiple points along the fibre length to measure the step height of individual scale edges. This data helps mills predict the shrink resistance and processing behavior of different wool lots before they enter the scouring and combing stages.
Processing Impact
Industrial chemical treatments like chlorination or enzyme application reduce scale protrusion to create machine-washable wool. Lowering the cuticular scale height minimizes fibre entanglement during washing. This reduction prevents shrinkage and ensures that the wool garment maintains its original dimensions over repeated laundry cycles.