Tag: "felting"

  • Genetic Variation of Merino Wool Felting

    Felting of wool is a major problem in the manufacture of knitted and woven products, as it is related to yarn shrinkage, which is a critical problem of the finished product. Felting is a unique property of animal fibres and a desirable characteristic in the making of felted products. However, felting is a particular problem with fine wools. Non-shrink woollen products are currently produced using chemical treatments during processing. Chlorination is the first step and it degrades the fibre surface. Fibres are then coated with polymers to cover degraded scale structures and/or to bond fibres together to prevent felt shrinkage. This process minimises frictional effects on wool fibre surfaces, limits relative motion of fibres in all directions, and increases hydrophilic properties of the fibre surface (Chen et al., 2000). Although these processes have been highly successful in shrink-proofing wool, they are expensive and detrimental to the fibre. Furthermore, the chlorination process is environmentally unfriendly and there are difficulties with residue disposal. Greeff and Schlink (2001) have shown that felting is a heritable trait, which implies that altering the ability of wool to felt through breeding may make a considerable contribution to wool’s processing properties and will enhance wool’s clean and green image. However, felting is strongly influenced by fibre curvature, fibre diameter (Scheepers and Slinger, 1968 ; Hunter et al., 1982 ; Kenyon et al., 1999 ; Veldsman and Kritzinger, 1960) and clean yield (Schlink et al., 2000). Lipson and Rothery (1975) showed that Merino wool has a significantly higher felting ability than Polwarth wool in spite of the fact that there were no differences in fibre surface friction, scale frequency or elastic properties between the breeds.They did note significant differences between the breeds in “swellings and necks” at intervals along the fibres, but conclusions were not clear because these wools differed in micron and curvature was not recorded. The OFDA2000 (Brims, 1997) has algorithms to measure variability and unevenness traits along the fibre which may be used to identify samples that may cause spinning problems. The objective of this study was to identify whether these along fibre variability traits influence felting and whether they are heritable. more »
  • A Comparative Study on the Felting Propensity of Animal Fibers

    The felting propensity of different animal fibers, particularly alpaca and wool, has been examined. The Aachen felting test method was employed. 1 g of each type of fiber was soaked in 50 ml of wetting solution and agitated in a dyeing machine to make felt balls. The diameter of each ball was measured in nine directions and the ball density was calculated in g/cm3; the higher the density value of the ball, the higher the feltability of the fibers. The effects of fiber diameter and fiber length on the felting propensity of these fibers were investigated. The results show that the alpaca fibers felt to a higher degree than wool fibers, and short and fine cashmere fibers have lower felting propensity than wool fibers at a similar diameter range. There is a higher tendency of felting for bleached and dyed alpaca fibers than for untreated fibers. Fiber length has a remarkable influence on the propensity of fiber felting. Cotton and nylon fibers were also tested for felting propensity to verify the mechanism responsible for the different fiber felting behavior. more »