Michel Victor Hubert Hick

Descriptive differential attributes of type of fleeces in Llama fibre and its textile consequence: 1 – Descriptive aspects

Abstract The Llama fleece types, subjectively defined as styles, are described objectively through different types of fibres, which differentiate each other in length, thickness, type of waves, and presence–absence of lustre. Repeatability of styles and fleece types objectively defined is high. Fleece types can be redefined as double coated and single coated; lustre and hemilustre; intermediate coated as intermediate between lustre and single coated; and intermediate between single coated and double coated, respectively. The differentiation is carried out among the most representative types of fibres of each fleece type considering that the frequency of these fibre types does not influence greatly in the differentiation.

Descriptive differential attributes of type of fleeces in llama fibre and its textile consequence. Part 2: consequences of the dehairing process

One of the quality characteristics most demanded from animal fibres is skin comfort or the effect the garment fibres have on the wearer’s skin. This comfort (or absence) is the product of the quantity of protruding fibre ends in contact with the epidermis. The fibre of mixed fleeces (fine and coarse fibres), such as llama fleeces, requires a special textile process for the garments made from them to be comfortable. This process is known as dehairing. It has different effects according to the fleece type used. Dehairing results in the structural change of the raw material since it extracts the coarser, longer and straighter (objectionable) fibres, thus affecting the rest of the textile processing, whether worsted or woollen. This research was designed to test the effect of fleece types on llama fibre dehairing performance, yield, bulk and sensorial attributes. Lustre fleeces have less bulk capacity and double‐coated fleeces, a lower overall yield due to a higher coarse fibre dehairing loss. Dehairing reduces the ‘prickle’ sensation, fundamentally with double‐coated fleeces and less notably with single‐coated non‐lustre fleeces, whereas with lustre fleeces no effect is detected. These results show that fibre classification by fleece type is fundamental when processing Argentine llama fibres.

Conceptual description of the llama fleece structure and the potential of classing and dehairing

For an overall description of llama fiber, its fleece structure and differences between fleece types are illustrated schematically, defined through a resumed evaluation, and determined as a compound of different fiber types. A dissection method is described and 252 samples of llama fleeces were dissected forming three fiber groups, within which fine, medium, and coarse fibers are gathered separately and, therefore, a dehairing process is simulated. Taking the group of fine fibers as a reference for the product to be obtained by dehairing, an average dehairing yield of 69% was calculated, which varies depending on the fineness of the fleece. The following fiber attributes were analyzed: fiber diameter, fiber length, crimp frequency, and crimp type. These were evaluated within fiber groups and among fleece types. The process of fleece classing regarding fineness is simulated through successively excluding coarse fleeces when evaluating the results. As a step previous to dehairing, and in order to assemble the most homogenous raw material, the necessity of fleece classing regarding fineness and type was confirmed. Fleece classing regarding fineness including only fleeces with a total mean fiber diameter lower than 28 µm and a subsequent dehairing process resulted in a mean of 21.6 µm for the group of fine fibers, with 96% of the fleeces with a mean fiber diameter of the group of fine fibers lower than 25 µm and 61% lower than 22 µm. We conclude that this segment of fine fibers reflects the potential of llama fiber as a textile raw material.