The Effect of Treatment with Perchloroethylene on the Abrasion Resistance of Wool Fabric

Abstract

The Martindale flat‐abrasion resistance (MAR) of lightweight wool worsted fabric is improved by treatment with non‐polar chlorinated solvents, including perchloroethylene. The rate at which the improvement is obtained with perchloroethylene is temperature dependent, but the optimum effect is obtained only by prolonged extraction, even at high temperature (e.g. 2 h at 80°C). A small increase in MAR is, however, obtained by solvent scouring in a commercial dry cleaning machine at 30–35°C. The improvement in MAR induced by treatment with perchloroethylene has been shown to involve extraction of internal lipids. The most likely source of the lipids is the cell membrane complex; their removal is believed to improve MAR because of a subsequent increase in intercellular adhesion. The improvement in MAR obtained by perchloroethylene treatment is stable to mild finishing procedures, but the magnitude of the improvement is decreased by dyeing at the boil. However, except for samples dyed at pH values less than pH 3, the MAR values of the solvent‐treated samples are higher than the values for the untreated and dyed‐only material.

Lipid Role in Wool Dyeing

“…This observation appears to be inconsistent with the fact that the anhydrous treatment is confined to the fiber surface, where it removes the F-layer from the epicuticle (Rippon & Leeder, 1986). The anhydrous alkali treatment would, however, be expected to remove lipids from the CMC at the point where this component extends to the fiber surface (Joko et al, 1985).…”

“…Leeder and Rippon (Leeder & Rippon, 1982) have shown that the CMC swells in formic acid to a much greater extent than does the whole fiber. They suggested (Rippon & Leeder, 1986) that this disproportionately high swelling is the reason why dye is taken up very rapidly from concentrated formic acid. The situation regarding the pathway for the dye diffusion into wool remained unresolved until the study by Leeder et al (Leeder et al, 1985b) involving the transmission electron microscope, described above.…”

Challenges in Wool Fiber Dyeing

“…Influence of Dye Bath pH on Fibre Damage: The ionic interactions in stabilizing the structures of wool fiber mainly depend up on the dye path pH. The significance of dye bath pH on fiber damage throughout dyeing has been renowned in various reviews [16,[58][59][60]. When wool is dyed within the iso-electric region of the fibre the intensity of damage is kept back to a bare minimum amount.…”