Wool treatments: from scouring to superwash, dyes and labels

What wool treatments are

A wool treatment is any chemical or physical process applied to wool between the sheep and the finished product, whether to clean it, make it easier to process, colour it or change how it behaves. A few terms recur throughout this guide.

• Scouring is the first wash of the raw wool, which removes grease (lanolin), dirt and sweat.
• Carbonising removes vegetable matter, such as burrs and seeds, from heavily contaminated wool, usually with acid.
• Finishing covers the treatments applied to yarn or fabric at the end of processing, for example to stop wool felting and shrinking.
• Superwash is the most common anti-shrink finish. It removes or reduces the scales on the wool fibre and coats the fibre in a polymer resin.
• Lanolin is the waxy substance sheep produce to weatherproof their fleece.
• APEOs (alkylphenol ethoxylates) are chemicals used in detergents, spinning oils, softeners and dye auxiliaries. They are endocrine disruptors, and their use is restricted in the EU.
• Micron is the measure of fibre diameter: the lower the number, the finer the fibre.

This guide is written from the Good Wool Collective’s January 2025 session on wool treatments in the value chain and its summary. It is general information, not a test protocol or legal advice.