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Machine washable wool: what it is, how sustainable it is and what to look out for

One of the questions that most frequently comes up in our community group centers around the sustainability of machine washable wool. Most often folks ask specifically about "superwash" wool and what exactly that is. But "superwash" is just one of the methods of treating virgin wool and so I always struggle to explain the "backstory" so to speak in as detailed a way as I can without overwhelming folks with journal articles and wads of information. So... in short, I've attempted to answer question on the topic of machine washable wool more broadly in this post. Here goes.....

As all seasoned woolies know, wool, a cherished natural fiber, has long been celebrated for its warmth, durability, and moisture-wicking properties. Traditional wool care often involved delicate handling, making it seem high maintenance. However, the advent of machine washable wool has revolutionized the industry, blending the benefits of wool with the convenience of machine washing. In this blog post, I'm going to delve into what machine washable wool entails, its sustainability, and what to consider when opting for this modern adaptation of a timeless fabric.

What Is Machine Washable Wool? Machine washable wool is traditional wool that has undergone a treatment process to enable it to withstand machine washing. This process involves applying a protective layer, typically a polymer or resin, onto the wool fibers. This coating shields the wool from felting or shrinking when exposed to water and agitation in washing machines. The aim is to make wool garments more convenient and easier to maintain without compromising their natural properties.
Sustainability of Machine Washable Wool Wool, in its natural state, is an environmentally friendly and renewable fiber. The introduction of machine washable wool presents both challenges and opportunities in terms of sustainability. The eco-friendliness of machine washable wool depends on the specific processes and chemicals used in the treatment. Here are some of the main treatment processes out there and what to look out for with each:

  1. Superwash Process: The superwash treatment method is one of the most common processes used to make wool machine washable. It involves treating wool with chlorine or an acid solution to remove the outer scales on the wool fibers that cause felting. Then, a polymer resin is applied to the fibers, forming a protective layer to prevent felting when the wool is machine washed. While the superwash method enhances the washability of wool, it's criticized for its use of chlorine, which can be harsh and environmentally damaging if not managed properly.

  2. Plasma Treatment: Plasma treatment is a more environmentally friendly alternative used to make wool machine washable. This process utilizes low-temperature plasma, which alters the surface of the wool fibers to reduce the scales that cause felting. It creates a smoother surface without the need for harsh chemicals. Plasma treatment shows promise in maintaining the natural qualities of wool while making it suitable for machine washing. It's often regarded as a more sustainable method compared to traditional superwash processes due to its reduced chemical usage. At The Green Kid, we stock plasma treated wool by the Menique brand.

  3. Enzyme Treatments: Enzyme treatments involve using specific enzymes to modify the surface of the wool fibers. These enzymes break down the scales on the wool fibers that cause felting, resulting in a smoother surface. This process is known for being more environmentally friendly compared to the superwash method because it uses biological catalysts rather than harsh chemicals.

  4. Polymer Coating: Similar to the superwash process, a polymer coating involves applying synthetic resins to the wool fibers to create a protective layer. This layer helps prevent felting and shrinkage during machine washing. The impact on sustainability can vary based on the specific chemicals used in the resin and their biodegradability.

  5. Hybrid Processes: Some manufacturers may use a combination of different treatments, such as a hybrid approach that involves a combination of enzyme treatment and polymer coating. These hybrid methods aim to maximize the benefits of each treatment while minimizing their individual drawbacks, seeking a balance between performance and sustainability.

The choice of treatment process often depends on the manufacturer's preference, cost-effectiveness, and the desired characteristics of the final product. Each treatment method has its own set of advantages and potential drawbacks in terms of sustainability, environmental impact, and the retention of wool's natural properties.

Compromise in Natural Properties One of the debates surrounding machine washable wool revolves around whether the additional treatments compromise its natural properties. While the addition of this protective layer might subtly impact the fabric's feel, studies suggest that it does not entirely compromise the core attributes that make wool highly desirable. Wool is renowned for its breathability, ability to regulate temperature, and excellent moisture-wicking properties. Research indicates that these inherent benefits of wool are not entirely lost during the process of making it machine washable.The treated wool may feel slightly different due to the added layer, which could influence its texture or drape. However, crucial characteristics such as breathability, moisture-wicking capabilities, and warmth retention generally remain intact, albeit potentially slightly modified.

The ongoing debate revolves around finding a balance between enhancing the ease of care for wool garments and maintaining the integrity of wool's natural properties.

What to Look Out For When considering machine washable wool, several factors merit attention. The use of eco-friendly treatments in the production process is crucial for minimizing environmental impact. Certifications such as GOTS , OEKO-TEX, RWS indicate a commitment to responsible production methods and the use of sustainable treatments. It's essential to follow the manufacturer's care instructions diligently to maintain the quality and longevity of the garment. Additionally, transparent brands that disclose their treatment processes and prioritize sustainable practices offer consumers an informed choice.

My final word on the matter.... Machine washable wool bridges the gap between the natural benefits of wool and modern convenience. The sustainable aspects of this innovation are promising, with lower water consumption, renewable materials, and a reduced need for harsh chemical treatments. While the debate continues regarding the compromise of natural wool properties, recent studies suggest that the alteration due to the protective layer is minimal, preserving most of wool's intrinsic characteristics. The decision to embrace machine washable wool or opt for traditional wool care methods should align with personal preferences, balancing convenience with the desire to maintain the authenticity and natural properties of this cherished fiber. My suggested approach or rather choice as a stockist and owner of The Green Kid is to marry both convenience and sustainability considerations and opt for OEKO-TEX certified plasma treated machine washable wool. I do promise to keep on top of the latest innovations and continue to seek out the most sustainable and convenient methods for our customers.

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