Innovation Exchange challenge: Alternatives for moth treatment in wool

The Innovation Exchange is supporting Wool Insulation Wales, through the InnovateUK KTN Net Zero Catalyst programme to find better solutions for moth protection of wool. Wool Insulation Wales wishes to engage innovators to find a moth protection solution that does not rely on harmful chemicals to work. The solution provider will be able to access part of a £25,000 grant award to work with Wool Insulation Wales on delivery of a proof-of-concept trial.

Background to the challenge

Wool Insulation Wales (WIW) aims to develop, manufacture and supply Welsh sheep’s wool thermal and acoustic insulation products on a large scale. These are both rolled loft insulation and insulation for use in wall panels.

WIW predominantly will serve housing associations and industrial or commercial property owners that when buying wool insulation, gain an extra metric by which they can measure their ESG goals. Large scale users of WIW products can also boast green supply chain credentials because the primary producers of wool are located in local rural economies. WIW has ambitious future volume targets for its product.

Moths

Species of moths that attack wool are commonly called ‘clothes’ or ‘carpet’ moths depending on where they are found and what fabrics they target. The moths are looking for animal-based fibres to lay their eggs because the larvae feed on keratin, a protein found in animal fibres, and also in dust. There are two main moth species that cause most of the damage to clothing and home textiles – the Webbing (or Common) Clothes Moth and the Case-bearing moth. More details on their life cycles and the damage they cause are available at the link below.

Wool insulation and anti-moth treatment

Using wool for building insulation enables the construction industry to meet its carbon targets in a safe and sustainable way, as part of the circular economy. It has a short value chain, with most wool production coming from the same places. 70% of UK Wool is traded through British Wool.

Raw wool is first of all scoured by major scouring plant operators before arriving to WIW for production of insulation. Scouring involves the following stages:

• 5 washes at temperatures ranging from 55-73C with a total immersion time of 7 minutes
• The First three tanks are charged with a biodegradable alcohol ethoxylate detergent and sodium carbonate
• The final tank is controlled to a neutral pH by the addition of formic acid
• The wool is then passed through a dryer at temperatures ranging from approximately 65-95 degrees centigrade for a period of approximately 3 minutes.

During the last stage of washing, the material is treated with anti-moth agents (typically borax or permethrin) in the coolest of a series of washes. The final wool material is provided to WIW, that creates its final product (see figure 1), in a similar way to felt matting.

Borax is the main anti-moth treatment used for wool insulation, with different treatments being appropriate for different use cases (e.g. clothing). Borax works by desiccating the moth larvae within the wool. Historically, many different types of chemicals were used for moth treatment, but many cannot be used now due to Health, Safety and Environmental (HSE) regulations.

The challenge

Current methods of using Borax or Permethrin are not environmentally friendly and risk being banned in the future. WIW would like to find an alternative form of moth protection for its wool insulation product, to avoid the use of these chemicals. Solutions should consider the following factors:

• Variability – It is expected that different solutions would work for different applications. Anti-moth treatment for wool insulation may not be appropriate for textiles, carpets and mattresses, for example. Borax is currently mainly used for insulation and clothing.
• Non-Flammable – Wool is naturally flame retardant and the use of anti-moth treatments can impact this. Any solution cannot compromise the flame retardant properties of wool.
• Insulative properties – Any solution should not compromise the insulative properties of wool.
• Environmental footprint – Any solution should aim to improve the current environmental footprint of wool insulation, rather than increase its impact.
• Toxicity – Any solution should aim to be non-toxic and ideally not a skin irritant. There are moth testing laboratories in the UK and any solution would need to be pass tests at these facilities. This would form part of the final demonstration project.
• Moth prevention accuracy – Any solution does not need to be absolutely perfect in combatting moth infestations but it must be competitive with Borax usage.
• Applying scents – Any smells that are applied to the wool as a form of moth deterrent will need to be in place for the duration of a product’s life. This will be decades at the least.
• Malleability – The insulation material is matted and rolled out. It needs to remain cuttable and able to be rolled out by a construction worker.
• Density – The wool material needs to remain at a certain density otherwise it limits the usage. For example, if it is too stiff, it will only be useable for wall panels rather than rolled loft insulation.
• Washability – Although not applicable to wool insulation, if the applicant is considering wider uses of its product, it should consider the ability to wash the wool. Wool that is treated with Borax can be washed currently.
• Cost competitive – Any solution should be cost competitive with Borax, which currently costs £0.82-£1.23 per kg of wool treated.

WIW has already investigated this field but has not been successful in finding a commercially available alternative to Borax. Areas that a solution provide may consider:

• Non-chemical treatments, such as ionic treatment
• Biological treatments that seek to prevent moths from laying eggs
• Treatment by nanoparticles e.g. nano-kaolinite?

WIW will be able to work with the winning solution provider to provide wool samples, so it can test its solution in a moth-testing laboratory in the UK.

Eligibility

Entrants to this competition must:

• Be SMEs or individual entrepreneurs
• Be UK based or have the intention to set up a UK base
• Have not exceeded its Minimum Financial Assistance limit (or De Minimis, where relevant).