Herculean effort
The team at New Zealand-based TMC spent five years looking for a way to add durability to wool garments without relying on synthetics. The answer was closer than they thought.
“Why do garments made from merino wool-based Nuyarn need to have a synthetic core, when it makes the fabric noisy and reflective?” asked the CEO of a big outdoor brand during a conversation with Andy Wynne, CEO of TMC (The Merino Company) and maker of Nuyarn. “It’s simply to add durability,” Mr Wynne replied – but it got him thinking.
For the next five years, the team at TMC in New Zealand tested ways to add strength to Nuyarn. It is a spinning technology the company acquired in 2013, after using it for several years and recognising the potential in the novel technique. Merino wool has many natural performance benefits, including thermoregulation, breathability and anti-odour properties, but the traditional ring-spinning way of creating the yarn inhibits some of these natural qualities, according to TMC.
Rather than spinning with a twist, Nuyarn’s specially designed machinery drafts merino fibres along a high-performance filament, resulting in two-ply yarns with more volume and aeration. This offers some substantial benefits, according to the company: the fabric dries five times faster, has 85% more elasticity, 35% more thermal retention, is 53% more air resistant, has 50% more burst strength and 120% more seam strength.
“There’s a direct correlation between elasticity and comfort,” says Mr Wynne. “The clothing industry tends to use elastane, spandex or Lycra, but these absorb moisture and retain it. Nuyarn has a mechanical stretch that is a consequence of the spinning technique and is there for the life of the product. The likelihood of developing a hole is also significantly reduced because there are no weak points due to the twist-free technique.”
A top made from Nuyarn would be 8.8 times more durable than an equivalent merino top, generating savings in raw materials, energy, transport and disposal. Added to this, the sheer speed of the spinning (250 metres per minute, up to 16 times faster than traditional machines) means 73% less energy is used, according to TMC’s measurements. What these numbers mean is that clothing made of Nuyarn offers extra performance attributes, making the material highly suitable for the sports and outdoorwear sectors in both winter and summer categories.
Outdoor brands that have chosen Nuyarn include The North Face, Salewa and Ortovox. Swiss brand Odlo won the Base Layer Award at ISPO 2022 for its Nuyarn-based Revelstoke PW 150 Base Layer, and US brand Pinebury selected it for its cycling apparel launch this summer, with founder Kyle Rancourt describing the fibre’s potential as “boundless”.
Innate strength
So far, so impressive. But TMC was determined to find an alternative to the nylon core for durability and to offer brands increased options. The team tested fabrics with Dyneema and Kevlar but the resulting material was too tough to cut. “We stumbled upon the flooring industry – it intrigued us that there was a natural fibre that had such a high degree of durability,” says Mr Wynne. However, the New Zealand strong wool (or carpet wool) was not suitable for clothing, or easy to work with. Historically, this type of fibre has gone into interior textiles, flooring and upholstery. “We brought it into our facility at Nuyarn, but this material in the top form [raw material] was a significant longer fibre, so we had to modify our spinning machines.”
They found using the Nuyarn technique they were able to create a thinner yarn that produced fabrics with varying weights and performance levels, making it suitable for clothing, socks and even shoes. The material, Herculan, can be laminated or bonded to the sole of a shoe, or used in double-sided fabrics, with a merino layer next to the skin.
“We currently see the greatest benefit with the sock and footwear industry due to its high durability and moisture management,” says Mr Wynne. Replacing the polyamide in the toe and heel of a sock with Herculan increases the natural fibre content from around 50% to 80% and stops the slippage and the resulting blisters. Intertek Vietnam tested these socks with a Martindale abrasion test and it was not until a million rubs that a hole appeared. For comparison, the New Zealand transport sector stipulates abrasion resistance for its socks must be 40,000 rubs. “Abrasion resistance has been a big deliverable for us in this.”
TMC is also working with a backpack company to replace the shoulder straps and hip belts with Herculan, reducing the potential for slippage when wet and performing better next to the skin.
Farm gate
As well as being readily available, this industrial wool could provide a new income stream for sheep farmers. A byproduct of the food industry, it can be sold to the carpet industry but, with that sector increasingly dominated by synthetics such as polypropylene, the wool often ends up in landfill.
To set it in a global context, total wool production increased in 2022, helped by a record sheep population, according to the International Wool Textile Organisation. There was an 11% jump in wool production in Australia, the largest wool-producing country, as it recovered from drought, but a 4.5% drop in New Zealand, the third-largest producer, due to continued low prices for carpet wool. While production of Merino wool increased by 5.2%, production of the interior textiles wool was flat at 0.8%. Mr Wynne points out growers have historically got very poor prices at the farm gate for this inferior grade; “Herculan gives them a better return.”
Herculan’s potential did not go unnoticed by the judges at specialist publication Fast Company, which ranked TMC number six in its list of ‘Most innovative manufacturing companies of 2022’, “an honour” for Mr Wynne. “When we first started working to transition carpet wool into the apparel sector, everyone thought we were mad because it has never been done before. But we had a vision and were determined, and ultimately our team found the solution.”
TMC’s contacts within a vertical supply chain means the ability to supply from fibre to final product. Adding Herculan to the portfolio means it can also offer a way to supersede the nylon core for certain applications. “This is a really exciting initiative for us,” concludes Mr Wynne. “We believe it will have a positive effect on the wool industry as well as help deliver a new era of products that perform better and last longer.”
The novel spinning technique adds volume to the wool and creates a yarn that is 35% lighter: Nuyarn versus conventional merino.
CREDIT: TMC
