Crimping of Wool Fibers

Abstract

By employing differential staining under controlled conditions and by experiments on resist ance to chemicals, it is shown that wool possesses an inherent bilateral structure which runs the entire length of the fiber from root to tip. The similarity in behavior of wool, as shown in this study, to the formation of crimp in viscose rayon indicates that structural asymmetry may be re sponsible for the coiling and crimping nature of the wool fiber. Isolated single wool fibers show a pronounced tendency to coil; however, when movement is restricted by the proximity of other fibers in a lock or in mass, the result is the formation of crimp.

Theoretical Mechanism for Crimp

“…With this interpretation of the observations it seems reasonable to expect that the effectiveness of the gearing action in the paracortex (gp) will be different from that of the orthocortex (go). If gp is greater than go, AI will be greater in the para-than in the orthocortex, causing the paracortex to lie on the inside of the curved fibre, consistent with observation (Horio and Kondo 1953). Significant structural differences have been observed (Chapman 1976) between cells of the ortho-and paracortex in the suprabulb which could lead to a difference in the effectiveness of the gearing action in the two cell types.…”

“…The net result is that each bunch of microfibrils will be twisted into a spiral and each cortical cell will tend to shorten. In order that the paracortex should lie on the inside of the curved wool fibre, consistent with observation (Horio and Kondo 1953), it is necessary that the twisting of the microfibrils be more effective (e.g. less slippage between engaging cogs) in the para-than in the orthocortex.…”

“…The cortex commonly consists of two hemicylinders. Although other geometrical arrangements are also found (Amad and Lang 1957), this bilateral division of the cortex into two hemicylinders is the one which is usually associated with crimp (Horio and Kondo 1953). In such a case it is known that the cells divide and develop more rapidly on one side of the bulb than on the other (Fraser 1964).…”

Interfacial Polyelectrolyte Complex Spinning of Cellulose Nanofibrils for Advanced Bicomponent Fibers

“…[29][30][31] Recognition of the mechanism behind the crimping behavior of wool has led to wool-inspired synthetic self-crimping fibers and further to a number of approaches for reversibly crimping fibers, where differential swelling or thermal expansion of the different components were exploited, mostly described in patent literature, [33][34][35][36][37] whereas very few scientific publications on reversibly crimping fibers are available. 38,39 One attractive direction of applications for such fibers has been responsive textiles that are able to reversibly change air permeability. 40 The mentioned fibers have all been processed with conventional fiber spinning processes typically utilizing special spinnerets.…”

Monoclonal Antibodies to a Subfraction of Merino Wool High-tyrosine Proteins

“…Thirdly, the orthocortex is more accessible to penetration by dyes, both acidic and basic (Bradbury 1973). Horio and Kondo (1953) have correlated the asymmetry of the wool fibre cortex with crimping characteristics.…”