The raw wool it to be washed in hot, soapy (see soap, Tiffany Lee), waterfollowed by a rinse in scouring liquor (ingredients = alkaline lye, water, lime, sulphuric acid, and potash, a mix of potassium compounds), which is then followed more washings, in hot and cold water (switching every time).

equation for soap:

(C₁₅H₃₁COO₃)C₃H₅ + 3 NaOH -> C₁₅H₃₁COONa +
C₃H₅(OH)₃

Sodium MetabisulphiteThe hot water is intended to melt the wax (C₂₅H₅₂), and the cold water is used to balance the hot water, so that the wool does not dry out from the heat. Repeat the washing until the wool appears clean; chemical treatments can be added to facilitate, accelerate, or enhance the cleanliness of this process. For example, Sodium Metabisulphite (Na₂S₂O₅), is added to the scouring process to bleach the color of the wool, from a less yellow/beige color, to a closer shade to white.

figure 5: dyed wool

Once a wool is dyed (see dyes, Claire Han), Hydrogen Peroxide (H₂O₂) can be added in order to brighten the color.

Also, certain acids, for example, ascetic, formic, or sulphamic, can be added to balance the pH of the wool (which some times acts as a base).
After scouring come the process of carding, separating the fibers of the wool. The wool must pass through rollers covered in teeth, detangling, and taking out the clumps often found in wool; then its lays the fibers closely parallel to each other, which gives worsted system made wools such a sleek feel. The wool is teased several times, until it is fine enough to pass through a condenser, a machine where wool enters a circular conveyor belt. This rounds out the wool, and forces the fibers to link together, into a sliver. This chain of round fibers is wound around a spool, and it is now almost ready to be spun.

However, before it is ready to be spun, there are still a few more steps. Very similar to the first part of carding, is combing. Combing separates the short from the long fibers, and lays them parallel to each other. Next they are reconstituted into a top, another sliver. Then comes reducing, also known as drawing, where the tops, or slivers, areshaped into one. In order to do this properly, the string of connected tops, the roving, must stay a very consistent thin size. This allows the roving to be spun in the spinning wheel. The real effect of the spinning wheel is that it twists the yarn around in order to strengthen it. Now that the epidermis of the sheep has been transformed into yarn, clothing can be made, by knitting the yarn into sweaters, skirts, socks…etc.
Although these steps were specifically for producing worsted fabrics, the production of woolen fabrics is very similar. The only difference is that with woolen fabrics, you skip the step of combing, because the fibers are not to be paralleled.

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