Pre-treatment of wool

摘要

AFTER shearing, wool is mechanically treated to shake out dirt and open the fleece in order to improve the efficiency of subsequent scouring. The raw wool is then scoured by aqueous washing; solvent scouring is less widely practised. The most common treatments before colouring wool are 1.1 Raw wool scouring: aqueous and / or solvent washing; 1.2 Carbonising 1.3 Scouring (desizing treatment) 1.4 Fulling/crabbing/thermo fixing 1.5 Easy-care treatments and anti-felting, anti-shrinking treatments 1.6 Bleaching The washing of raw wool - so called raw wool scouring has several aims: 2.1 To remove natural impurities such as wool grease, suit (dried perspiration) and dirt; 2.2 To remove residues of insecticide, acaricides or insect growth regulators (veterinary medicines to protect sheep from ectoparasites, such as lice, mites, etc.) 2.3 To make the wool suitable for further processing When considering the ability of solving the different contaminants present in raw wool, one may be aware of the specificity of wool washing treatments. Wool grease is insoluble in water (but soluble in non-polar solvents such as dichloromethane or hexane) and needs addition of special surfactants to water. Suit arises from the secretion of the sweat gland in the skin and is soluble in polar solvent such as water and alcohol. Dirty materials present on raw wool can be mineral dirt, sand, clay, dust and organic materials.