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.
Effects of bleaching and dyeing on the quality of alpaca tops and yarns
This paper reports the effects of bleaching of alpaca tops and dyeing of bleached alpaca tops/yarns on the quality of tops and yarns. A dark brown alpaca top was bleached with hydrogen peroxide. Two bleaching methods were tried for effectiveness of color removal. A portion of each bleached top was dyed after bleaching. Color parameters were examined for unbleached, bleached and bleached/dyed tops, these tops were then converted into yarns of different twist levels and counts using a worsted spinning system. Some of the bleached yarn from each bleaching method was dyed in a package dye vat to compare the difference of top dyeing versus yarn package dyeing on yarn quality. Fiber diameter, yarn strength, yarn evenness, yarn hairiness and fiber degradation were tested to examine the effects of bleaching and dyeing on these properties at top and yarn stages. A processing route for bleaching and dyeing alpaca fiber was recommended.
Scaliness of Wool Fibres
ACCORDING to a theory of milling which was developed some years ago, fabrics are capable of undergoing milling shrinkage only when some or all of the component fibres possess a surface scale structure, are easily deformed, and show perfect recovery from deformation1. It should, therefore, be possible to make wool unshrinkable by modifying its elastic properties instead of by the customary method of attacking the surface-scale structure. The truth of this deduction has been established in a number of ways2,3,4. Perhaps the most convincing is the recent demonstration that woollen flannel can be made unshrinkable by treatment with mercuric acetate or benzoquinone4. Both reagents increase the resistance of the fibres to deformation; both increase the scaliness of the fibres, as measured in soap solution by means of the lepidometer5,6. In the light of these results it was concluded that mercuric acetate and benzoquinone make wool unshrinkable by modifying the elastic properties of the fibres, and not by attacking or masking the surface-scale structure.